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LFT, liver function test; OA, organic acids; TFT, thyroid function tests; TSC, tuberous sclerosis complex; UE, urea and electrolytes; VLCFA, very long chain fatty acids; WES, whole exome sequencing; WGS, whole genome sequencing; XLID, X linked intellectual disability genes. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 354 Part IV u Learning and Developmental Disorders Before making the diagnosis of ID, other disorders that affect cogni tive abilities and adaptive behavior should be considered. These include conditions that mimic ID and others that involve ID as an associated impairment. Sensory deficits (severe hearing and vision loss), com munication disorders, refractory seizure disorders, poorly controlled mood disorders, or unmanaged severe attention deficits can mimic ID; certain progressive neurologic disorders can appear as ID before regression is appreciated. Approximately half of children with cere bral palsy (see Chapter 638.1) and one third of children with autism spectrum disorder (see Chapter 58) also have ID. Differentiation of isolated CP from ID relies on motor skills being more affected than cognitive skills and on the presence of pathologic reflexes and tone changes. Importantly, cognitive testing may be limited because of motor and communication impairments in CP such that an accurate diagnostic assessment often hinges on evaluation by a professional with experience with this population. In ASD, social communication and social adaptive skills are more affected than nonverbal reasoning skills, whereas in ID, there are usu ally more equivalent deficits in social, fine motor, adaptive, and cogni tive skills. The discrepancy between social communication abilities and overall developmental abilities and the presence, severity, and intensity of restricted and repetitive behaviors differentiates whether an individ ual has ID alone or a comorbid diagnosis of ASD. Among toddlers with ASD, those with lower verbal and nonverbal cognitive test scores in conjunction with poor adaptive skills have an 8590 chance of being classified as having ID in adulthood. However, across all levels of cog nition in ASD, there is a significant trend toward much lower adaptive functioning than would be expected otherwise. Table 56.7 Suggested Evaluation of the Child with Intellectual Disability (ID) or Global Developmental Delay (GDD) TEST COMMENT In depth history Includes prenatal, perinatal, and postnatal events (including seizures); developmental attainments; and three generation pedigree in family history (focusing on neurologic or developmental abnormalities, miscarriages, consanguinity, etc.) Physical examination Particular attention to minor or subtle dysmorphisms; growth issues; neurocutaneous findings; eye and skull abnormalities; hepatosplenomegaly; and neurologic examination for focality Behavioral phenotype Vision and hearing evaluation Essential to detect and treat; can mask as developmental delay Gene microarray analysis A 15 yield overall Better resolution than with karyotype; may identify up to twice as many abnormalities as karyotyping Often included in exome testing Karyotype No longer a first line test Reserve use when concerned for trisomicmonosomic conditions, inversions and balanced insertions, or reciprocal translocations Fragile X screen Combined yield of
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2, preselection on clinical grounds can increase yield to 7.6 Next generation gene sequencing Detects inherited and de novo point mutations, especially in nonsyndromic severe intellectual disability Whole exome sequencing gives an additional yield of about 3040 Pilot studies of whole genome sequencing (WGS) reveal additional yield of about 15 Neuroimaging MRI preferred; positive findings increased by abnormalities of skull contour or microcephaly and macrocephaly or focal neurologic examination (3040 if indicated, 1014 if screening) Identification of specific etiologies is rare; most conditions that are found do not alter the treatment plan; need to weigh risk of sedation against possible yield Thyroid (T4, TSH) Near 0 in settings with universal newborn screening program Serum lead If there are identifiable risk factors for excessive environmental lead exposure (e.g., low socioeconomic status, home built before 1950) Metabolic testing Yield of 0.24.6 based on clinical indicators and tests performed Urine organic acids, plasma amino acids, ammonia, lactate, and capillary blood gas Focused testing based on clinical findings is warranted if lack of newborn screen results or suggestive historyexam (e.g., regression, consanguinity, hepatosplenomegaly, course facies) Tandem mass spectrometry newborn screening has allowed for identification of many disorders in the perinatal period and has decreased yield in older children; other disorders have emerged, such as congenital disorders of glycosylation (yield 1.4) and disorders of creatine synthesis and transport (yield 2.8) MECP2 for Rett syndrome 1.5 of females with criteria suggestive of Rett (e.g., acquired microcephaly, loss of skills) 0.5 of males EEG May be deferred in absence of history of seizures or significant language regression Repeated history and physical examination Can give time for maturation of physical and behavioral phenotype; new technology may be available for evaluation EEG, Electroencephalogram; CGH, comparative genomic hybridization; MECP2, methyl CpGbinding protein 2; T4, thyroxine; TSH, thyroid stimulating hormone. Data from Michelson DJ, Shevell MI, Sheer EH, et al. Evidence report. Genetic and metabolic testing on children with global developmental delay: Report of the Quality Standards Subcommittee of the American Academy of Neurology and the Practice Committee of Child Neurology. Neurology. 2011;77:16291635; Curry CJ, Stevenson RE, Aughton D, et al. Evaluation of mental retardation: Recommendations of a Consensus Conference: American College of Medical Genetics. Am J Med Genet. 1997;12:72:468477; Shapiro BK, Batshaw ML. Mental retardation. In: Burg FD et al: Gellis and Kagans Current Pediatric Therapy, 18th ed, Philadelphia: Saunders; 2005; and Shevell M, Ashwal S, Donley D, et al. Practice parameter: Evaluation of the child with global developmental delay. Neurology. 2003;60:367380. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 56 u Developmental Delay and Intellectual Disability 355 Ketothiolase Deficiency Urine Organic Acids (n22) Urine Glycosaminoglycans (n7) Urine Creatine Metabolites (n3) Urine Oligosaccharides (n2) Urine Purines Pyrimidines (n2) Plasma AminoAcids (n13) Blood Tests Urine Tests Plasma Total Homocysteine (n9) Cobalamin A Deficiency Cobalamin B Deficiency Cobalamin C Deficiency (tHcy) Cobalamin D Deficiency (tHcy)
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Cobalamin F Deficiency (tHcy) Ethylmalonic Encephalopathy (ACP) Glutaric Acidemia type I Hunter syndrome (MPS II) AGAT deficiency GAMT deficiency Mannosidosis Pyrimidine 5nucleotidase superactivity Molybdenum Cofactor Type A deficiency I.o. Argininosuccinic Aciduria HHH syndrome I.o. OTC Deficiency Phenylketonuria PDH Complex Deficiency Tyrosinemia type II (UOA) Maple Syrup Urine Disease (Variant) I.o. MTHFR Deficiency (tHcy) I.o. NAGS Deficiency I.o. Citrullinemia I.o. Citrullinemia Type II I.o. CPS Deficiency I.o. Argininemia Homocystinuria (UOA) Cobalamin E Deficiency Cobalamin F Deficiency (UOA) Cobalamin G Deficiency I.o. MTHFR Deficiency (PAA) Cobalamin C Deficiency (UOA) Cobalamin D Deficiency (UOA) Aspartylglucosaminuria Transporter Defect Creatine Hurler syndrome (MPS I) Sanfilippo syndrome (type a, b, c, d) Sly syndrome (MPS VI) Glutaric Acidemia type II HMGCoA Lyase Deficiency MHBD Deficiency mHMGCoA Synthase Deficiency I.o. Propionic Acidemia (ACP) SCOT Deficiency SSADH Deficiency Tyrosinemia type II (PAA) Holocarboxylase Synthetase Deficiency Homocystinuria I.o. Isovaleric Acidemia (ACP) 3Methylcrotonyl Glycinuria (ACP) 3Methylglutaconic Aciduria I.o. Methylmalonic Acidemia (ACP) Fig. 56.2 Summary of treatable inherent errors of metabolism (IEM) that can be detected by metabolic tests in affected children, each of which is affordable and accessible and has the potential to identify at least 2 IEM (and up to 22). Each bar represents the yield of the specific screening test and lists the number and types of treatable IEM it can identify. PAA, Plasma amino acids; tHcy, total homocysteine; ACP, plasma acylcarnitine profile; UOA, urine organic acids. (From van Karnebeek CD, Stockler S. Treatable inborn errors of metabolism causing intellectual disability: A systematic literature review. Mol Genet Metab. 2012;105:368381, Fig. 1, p. 374.) Table 56.8 Treatable Intellectual Disability Endeavor (TIDE) Diagnostic Protocol TIER 1: NONTARGETED METABOLIC SCREENING TO IDENTIFY 54 (60) TREATABLE IEM Blood Plasma amino acids, total homocysteine, acylcarnitine profile, copper, ceruloplasmin Urine Organic acids, purine and pyrimidines, creatine metabolites, oligosaccharides, glycosaminoglycans, amino acids (when indicated) TIER 2: CURRENT PRACTICE ADHERING TO INTERNATIONAL GUIDELINES (ONE OR MORE OF THE FOLLOWING) Blood Cytogenetic testing (array CGH), thyroid studies, complete blood count, lead, metabolic testing, fragile X, targeted gene sequencingmolecular panel Diagnostics Brain MRI and 1H spectroscopy (where available) Referrals Audiology, ophthalmology TIER 3: TARGETED WORKUP TO IDENTIFY 35 (40) TREATABLE IEM REQUIRING SPECIFIC TESTING According to patients symptomatology and clinicians expertise Use of digital tools (www.treatable id.org) Blood Plasma cholestanol, 7 dehydroxycholesterol:cholesterol ratio, pipecolic acid and urine amino adipic semialdehyde (AASA), very long chain fatty acids Plasma vitamin B12 and folate, serum lactate to pyruvate ratio, whole blood manganese CSF Lactate to pyruvate ratio, amino acids, neurotransmitters, CSF to plasma glucose ratio Urine Urine deoxypyridinoline Other Enzyme activities (leukocytes): arylsulfatase A, biotinidase, glucocerebrosidase, fatty aldehyde dehydrogenase CoQ measurement: fibroblasts Molecular analysis: CA5A, NPC1, NPC2, SC4MOL, SLC18A2, SLC19A3, SLC30A10, SLC52A2, SLC52A3, PDHA1, DLAT, PDHX, SPR, TH genes Low threshold for ordering tests. IEM, Inborn errors of metabolism; CSF, cerebrospinal fluid; CGH, comparative genomic hybridization; CoQ, coenzyme Q (ubiquinone). Adapted from Van Karnebeek CD, Stockler Ipsiroglu S. Early identification of treatable inborn errors of metabolism in children with intellectual disability: The Treatable Intellectual Disability Endeavor protocol in British Columbia. Paediatr
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Child Health. 2014;19(9):469471. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 356 Part IV u Learning and Developmental Disorders DIAGNOSTIC PSYCHOLOGIC TESTING The formal diagnosis of ID requires the administration of individual tests of intelligence and adaptive functioning. The Bayley Scales of Infant and Toddler Development, Fourth Edition (BSID 4), the most used infant intelligence test, provides an assessment of cognitive, language, motor, behavior, social emotional, and general adaptive abilities between 16 days and 42 months of age. The BSID 4 correlates more strongly with other standardized tests of cognition and motor development than did prior versions of the test and permits the differentiation of infants with severe ID from typically developing infants, but it is less helpful in distinguishing between a typical child and one with mild ID. The most used intelligence tests for children older than 3 years are the Wechsler Scales, although others are also used. The Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI IV) is used for children with mental ages of 2.5 7.6 years. The Wechsler Intelligence Scale for Children, Fifth Edition (WISC V) is used for children who function above a 6 year old mental age. Both scales contain numerous subtests in the areas of verbal and perfor mance skills. Although children with ID usually score low on all subscales, they occasionally score in the average range in one or more performance areas. Among children who have marked lan guage or verbal limitations, tests like the Differential Ability Scales II (DAS II) or the Leiter International Performance Scale, Third Edition (Leiter 3) may be used to optimally capture nonverbal per formance skills. Several normative scales are used in practice to evaluate adaptive functioning, often through questionnaire or interview formats, with information being attained from caregivers and educators in mul tiple different environments when possible (home, school, work). For example, the Vineland Adaptive Behavior Scale (VABS 3) uses semi structured interviews with parents and caregiversteachers to assess adaptive behavior in four domains: communication, daily living skills, socialization, and motor skills. Other tests of adaptive behavior include the Adaptive Behavior Assessment System (ABAS 3), the Woodcock Johnson Scales of Independent BehaviorRevised, and the AAIDD Diagnostic Adaptive Behavior Scale (DABS). There is usually (but not always) a good correlation between scores on the intelligence and adaptive scales in ID. However, it is important to recognize that adaptive behavior can by influenced by environmen tally based opportunities and by family or cultural expectations. Basic practical adaptive skills (feeding, dressing, hygiene) are more responsive to remedial efforts than is the IQ score itself. The trajec tory of adaptive skill acquisition may not be consistent over time because of the underlying condition, response to interventions, and environmental expectations. COMPLICATIONS AND ASSOCIATED CONDITIONS Children with ID have higher rates of vision, hearing, neurologic, orthopedic, and behavioral or emotional disorders than typically developing
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children (Table 56.9). These problems are often detected later in children with ID. If untreated, the associated impairments may adversely affect the individuals outcome more than the ID itself. The more severe the ID, the greater the number and severity of associated impairments. Knowing the cause of the ID can help predict which associated impairments are most likely to occur. For example, fragile X syndrome (see Chapter 59) and fetal alcohol syn drome (see Chapter 146) are associated with a high rate of behav ioral disorders and may be amenable to certain treatments. Children with fetal alcohol syndrome may have a less robust response to stimulant use, whereas preliminary data suggest that children with fragile X syndrome may see behavioral improvements with the use of metformin. Other genetic conditions may have well established medical comorbidities that should be screened for throughout the life span. For example, Down syndrome (see Chapter 57) has many medical complications (hypothyroidism, hearing and vision impair ments, obstructive sleep apnea, congenital heart disease, atlantoax ial subluxation). Such associated impairments can require ongoing physical therapy, occupational therapy, speech language therapy, behavioral therapy, adaptive and mobility equipment, glasses, hear ing aids, and medication or other medical management. Failure to identify and treat these impairments can hinder successful habilita tion and result in difficulties in the school, home, and neighbor hood environment. Special attention should be given to screening for accidental injury, neglect, and abuse. Children with ID have a greater risk of prevent able death from accidental injury. They are more likely to be victims of frequent, continual abuse at the hands of multiple abusers and are more frequently abused by unrelated or unfamiliar perpetrators compared to typically developing peers. Up to 1530 of children with ID are victims of sexual abuse, with female teens with ID being at highest risk. Abuse may precipitate the onset of maladaptive behaviors and changes in mood. As such, a high index of suspicion must be maintained, with the knowledge that even individuals with severe ID may be able to reliably disclose vic timization and abuse. PREVENTION Examples of primary programs to prevent ID include the following: u Increasing the publics awareness of the adverse effects of alco hol and other drugs of abuse on the fetus (the most common preventable cause of ID in the Western world is fetal alcohol ex posure). u Encouraging safe sexual practices, preventing teen pregnancy, and promoting early prenatal care with a focus on preventive programs to limit transmission of diseases that may cause congenital infection (syphilis, toxoplasmosis, cytomegalovirus, HIV). u Preventing traumatic injury by encouraging the use of safety tech nologies (car seats, window locks, helmets, gun locks). u Preventing poisonings by teaching parents about securing medica tions and potential poisons. Table 56.9 Conditions Associated with ID MEDICALPHYSICAL CONDITIONS DEVELOPMENTAL PSYCHIATRIC CONDITIONS Cerebral palsysevere motor impairment Attention deficithyperactivity disorder Seizures Endocrine abnormalities (e.g., hypothyroidism, short stature) GI issues (constipation, reflux) Dysphagia Other organ system anomalies (e.g., congenital heart disease, malformations) Hearing loss Vision impairment (refractive
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error, cataracts, strabismus) Dental caries Lead poisoning from associated pica Sleep disorders (OSA, behavioral sleep dysfunction) Obesity Emotional disorders (anxiety, mood disorders, posttraumatic stress disorder) Obsessive compulsive disorder Behavioral disorders (self injurious behavior, aggression, adjustment disorder, disruptive behavior) Autism spectrum disorder Eating and feeding disorders Psychotic disorders Movement disorders (tics, stereotypies,) Developmental coordination disorder Learning disabilities (difficulties not explained by cognition alone) Substance abuse Victimization (bullying, sexual abuse, physical abuse) GI, Gastrointestinal; OSA, obstructive sleep apnea. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 56 u Developmental Delay and Intellectual Disability 357 u Implementing immunization programs to reduce the risk of ID caused by encephalitis, meningitis, and congenital infection. Presymptomatic detection of certain disorders can result in treatment that prevents adverse consequences. State newborn screening by tandem mass spectrometry (now detecting 60 rare genetic disorders in most states), newborn hearing screening, and preschool lead poisoning prevention programs are examples. Addi tionally, screening for comorbid conditions can help to limit the extent of disability and maximize the level of functioning in cer tain populations. Annual thyroid, vision, and hearing screening in a child with Down syndrome is an example of presymptomatic testing in a disorder associated with ID. TREATMENT Although the core symptoms of ID can be prevented in some condi tions, they are generally not treatable once ID is diagnosed. Many associated impairments are amenable to intervention and therefore benefit from early identification. Most children with an ID do not have a behavioral or emotional disorder as an associated impair ment, but challenging behaviors (aggression, self injury, opposi tional defiant behavior) and internalizing disorders (mood and anxiety disorders) occur with greater frequency in this population than among children with typical intelligence. These behavioral and emotional disorders are the primary cause for out of home place ments, increased family stress, reduced employment prospects, and decreased opportunities for social inclusion. Some behavioral and emotional disorders are difficult to diagnose in children with more severe ID because of the childs limited abilities to understand, com municate, interpret, or generalize. Other disorders are masked by the ID. The detection of ADHD (see Chapter 50) in the presence of moderate to severe ID may be difficult, as may be discerning a thought disorder (psychosis) in someone with autism and ID. Behavioral disorders in ID often result from a mismatch between the childs abilities and the demands of the situation, organic problems, and family difficulties. These behaviors may represent attempts by the child to communicate, gain attention, gain access to desired tangibles, escape certain demands, exert control, or avoid frustration. Determining the antecedents, functions, and conse quences of behavior can help in developing an effective behavior intervention plan. The most formal iteration of this is a functional behavioral assessment carried out by a well trained behavior ana lyst. In assessing the challenging behavior, one must also consider whether it
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is inappropriate for the childs mental or developmental age, rather than the chronological age. However, if the behavior is dangerous to the individual or the external world, intervention is required regardless of whether it is appropriate for their develop mental age. When intervention is needed, an environmental change, such as a more appropriate classroom setting, may improve certain behavior problems. Behavior management techniques and parent training are valuable; psychopharmacologic agents may be appro priate in certain situations, such as aggression or self injurious behaviors with high levels of intensity and frequency. No medication has been found that improves the core symptoms of ID. However, several agents are being tested in specific disor ders with known biologic mechanisms (e.g., mTOR inhibitors in tuberous sclerosis and PTEN disorder), with the hope for future pharmacologic options that could alter the natural course of cogni tive impairment seen in patients with these disorders. Medication is most useful in the treatment of associated behavioral and psychi atric disorders that do not respond to initial behavioral approaches and environmental manipulation. Additionally, underlying medical disorders and abuseneglect should be considered as part of the dif ferential before medication initiation in patients with self injury, aggression, irritability, or significant disruptive behaviors. Medications used among individuals with ID generally target spe cific associated symptom complexes, including inattention, impulsiv ity, and hyperactivity (stimulant medications and alpha agonists); self injurious behavior and aggression (antipsychotics); anxiety, obsessive compulsive disorder, and depression (selective serotonin reuptake inhibitors); and sleep related dysfunction (melatonin, alpha agonists, gabapentin, trazodone). Even if a medication proves successful, its use should be reevaluated at least yearly to assess the need for continued treatment of the target behaviors and improve ments in functional goals. Generally, medications should be started at a low dose and increased slowly, with frequent assessments of whether benefits outweigh any adverse effects. Adverse effects and idiosyncratic responses to medications may be more common in this population. PRIMARY CARE, SUPPORTIVE CARE, AND MANAGEMENT Each child with ID needs a medical home with a primary care cli nician who is readily accessible to the family to answer questions, help coordinate care, and discuss concerns. Healthcare clinicians can have effects on patients and their families that are still felt decades later. The role of primary care includes involvement in prevention efforts, early diagnosis, identification and management of associated deficits, longitudinal developmental surveillance and screening, referral for appropriate diagnostic and therapeu tic services, interdisciplinary management, provision of anticipa tory guidance (see Chapter 13), and advocacy for the child and family. The management strategies for children with an ID should be multimodal, with efforts directed at all aspects of the childs life: health, education, social and recreational activities, behavior problems, and associated impairments. Support for parents and siblings should also be provided (Table 56.10). A strengths based approach focusing on optimizing participation in all aspects of life tends to be more beneficial than an exclusive focus on cognitive or academic skill attainment. Goals of overall care should include maximizing the individuals independent
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functioning, identify ing effective communication strategies, preserving and enhancing physical fitness and well being, supporting positive relationship building, and ensuring opportunities for the individual to partici pate fully in the community and find purpose and enjoyment in life activities. Goals should be individualized, flexible, appropriate, and attainable. The AAP has published a series of guidelines andor toolkits for health supervision of children with specific disorders associated with ID (Down syndrome, fragile X syndrome, Williams syndrome, fetal alcohol spectrum disorder). Another source for disorder specific information can be found at https:www.medicalhomeportal.orgd iagnoses and conditions. Goals should be considered and programs adjusted as needed during the primary care visit. Decisions should also be made about what additional information is required for future planning or to explain why the child is not meeting expectations. Other evalua tions, such as formal neuropsychologic or educational testing, can be helpful for diagnostic clarification, attaining more appropriate school based supports, understanding strengths and challenges, or assisting with the process of transition at various time points. Interdisciplinary Management The primary care clinician has the responsibility for consulting with other disciplines to make the diagnosis of ID and coordinate treat ment services. Consultant services may include speech language pathology, physical therapy, occupational therapy, psychology, audi ology, nutrition, nursing, and social work, as well as medical special ties such as neurodevelopmental disabilities, neurology, genetics, physical medicine and rehabilitation, psychiatry, developmental behavioral pediatrics, and surgical specialties. Contact with early intervention and school personnel is equally important to help pre pare and assess the adequacy of the childs individual family service plan or individual education plan. The family should be an integral part of the planning and direction of this process. Care should be family centered and culturally sensitive; for older children, their participation in planning and decision making should be promoted to whatever extent possible. Goal setting should be appropriate, individualized, and achievable Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 358 Part IV u Learning and Developmental Disorders Table 56.10 Resource List for Families by Category Advocacy Consortium for Citizens with Disabilities http:www.c c d.org The Arc https:thearc.org American Association on Intellectual and Developmental Disabilities https:www.aaidd.org Council for Exceptional Children https:exceptionalchildren.org The National Disability Rights Network https:www.ndrn.org Ollibean https:ollibean.com TASH https:tash.org National Association for Councils on Developmental Disabilities https:www.nacdd.org Assistive Technology Rehabilitation Engineering and Assistive Technology Society of North America www.resna.org AT Network www.atnet.org Association of Assistive Technology Act Programs (ATAP) www.ataporg.org Guide to Software Accessibility for the Disabled ithare.comguide to software accessibility for the disabled Behavior and Mental Health National Association for the Dually Diagnosed (NADD) www.thenadd.org Behavior Analyst Certification Board www.bacb.com Challenging behaviors in IDD informational article https:milnepublishing.geneseo.eduinstructi on in functional assessmentchapterchapter 1 challenging behaviors of individuals with developmental disabilities Challenging Behaviors Toolkit https:www.autismspeaks.orgsitesdefaultfiles2018 08Challenging20Behaviors20Tool20Kit.pdf Early Intervention Zero to Three www.zerotothree.org Pathways.org https:pathways.org First Signs Campaign http:www.firstsigns.org Early intervention overview https:www.parentcenterhub.orgei overview
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CDC Early intervention information https:www.cdc.govncbdddactearlyparentsstates .html CDC developmental milestones https:www.cdc.govncbdddactearlymilestonesind ex.html Special Education and Inclusion Parent Training and Information Centers (PTIs) https:www.parentcenterhub.orgfind your center Iris Center (Inclusion) https:iris.peabody.vanderbilt.edu Understood.org https:www.understood.orgpagesenlearning thinking differences WrightsLaw.com http:www.wrightslaw.comadvocltrsinclusionright suzanne.htm Institute for Community Inclusion http:www.communityinclusion.org Kids Included Together https:www.kit.orgwhat we doinclusion resources Kidstogether.org http:www.kidstogether.org Postsecondary Education PACER Center www.PACER.orgtransition National Center for College Students with Disabilities https:www.nccsdonline.org DREAM: Disability Rights, Education, Activism, and Mentoring https:www.dreamcollegedisability.org Guide to Paying for College for People with Disabilities https:lendedu.comblogpaying for college for people with disabilities Affordable Colleges Online College Resources for Students with Disabilities https:www.affordablecollegesonline.orgcolle ge resource centerresources for students with disabilities Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 56 u Developmental Delay and Intellectual Disability 359 Table 56.10 Resource List for Families by Categorycontd Transition, Vocational Training, Employment, and Community Participation The Arc https:thearc.org Best Buddies International https:www.bestbuddies.org Easter Seals https:www.easterseals.comEasterSeals.com Got Transition https:www.gottransition.org Project SEARCH https:www.projectsearch.usProject SEARCH Recruit Disability job listings https:www.recruitdisability.org Rehabilitation Services Administration https:rsa.ed.gov Work Incentives Planning and Assistance Project Fact Sheet https:www.ssa.govdisabilityresearchwigeneralinfo .htm Respectability https:www.respectability.orgresourcesJob Seekers Disabilities Employer assistance and Resource Network on Disability Inclusion https:askearn.org What Can You Do? Resources for Employers https:www.whatcanyoudocampaign.orgwhere to learn moreresources for employers Recreation Special Olympics https:www.specialolympics.org Summer camp locator https:www.veryspecialcamps.com Parent and Family Resources Family Voices https:familyvoices.orglfppf2fs Parents Helping Parents https:www.php.com Eparent.com http:www.eparent.com Community Parent Resource Centers (CPRCs) https:www.parentcenterhub.orgfind your center Summer camp options for siblings of children with IDD https:www.veryspecialcamps.comsummersiblings camps Government Initiatives and Services Policy information on SSI for children with disabilities https:www.cbpp.orgresearchsocial securityssi a lifeline for children with disabilities Supplemental security income and social security disability insurance beneficiaries with IDD https:www.ssa.govpolicydocsssbv77n1v77n1p1 7.html Centers for Medicare and Medicaid Services http:www.cms.gov Home and community based waiver programs https:www.medicaid.govmedicaidhome community based servicesindex.html Achieving a Better Life Experience (ABLE) Accounts ABLE national resource center https:www.ssa.govssispotlightsspot able. htmlhttps:www.ssa.govssispotlightsspot able.html https:www.ablenrc.org Association of University Centers on Disabilities http:www.aucd.orgdirectorydirectory.cfm Administration for Community Living https:acl.govwww.acl.govprogramsaiddindex.as px. Division on Developmental Disabilities (DDD) http:daddcec.orgHome.aspxwww.acl.govprograms aiddindex.aspx. National Association of States Directors of Developmental Disabilities Services (NASDDDS) http:www.nasddds.orgwww.nasddds.org http:daddcec.orgHome.aspx Division on Developmental Disabilities (DDD) Individual state websites Disorder Specific Groups Epilepsy http:www.epilepsyfoundation.org Autism www.autismspeaks.org www.autism society.org Cerebral Palsy https:www.yourcpf.org There are other disorder specific groups that are too numerous to list here, which include large national networks for more common syndromes such as Down syndrome (e.g., http:www.ndss.org, https:www.ndsccenter.org) or fragile X syndrome (http:www.fragilex.org) and smaller support groups for more rare disorders (many of which can be located through the unique website at https:rarechromo.org). Continued Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 360 Part IV u Learning and Developmental Disorders Periodic Reevaluation The childs abilities and the familys needs change over time. As the child grows, more information must be provided to
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the child and family, goals must be reassessed, and programming needs should be adjusted. A periodic review should include information about the childs health status and the childs functioning at home, at school, and in other community settings. Other information, such as psychologic or educational testing, may be helpful. Reevaluation should be under taken at routine intervals (every 6 12 months during early childhood), at any time the child is not meeting expectations, or when the child is moving from one service delivery system to another. This is especially true during the transition to adulthood, beginning at age 16, as man dated by the IDEA Amendments of 2004, and lasting through age 21, when care should be transitioned to adult based systems and providers (see Chapter 152). Federal and Education Services Education is the single most important discipline involved in the treatment of children with an ID. In the United States, the IDEA, Part B, mandates a free and appropriate public education (FAPE) in the least restrictive environment (LRE) for all school age children (3 21 years of age). Additionally, Part C mandates early interven tion services from birth through 36 months of age to be delivered in a natural environment (usually home) for all qualifying infants and toddlers. The developmental and educational program for children with GDD or ID must be relevant to the childs unique needs and address the childs individual strengths and challenges. The childs developmental level, requirements for support, and goals for inde pendence provide a basis for early intervention services to establish an individualized family service plan (IFSP), which focuses on the familys needs to help them optimize the development of their child. For children over 36 months of age, the school system devel ops an individualized education program (IEP), which focuses on the childs educational needs. Inclusive education seeks to sup port the right of every child, regardless of ability, to participate in a broad range of activities and contexts as full members of families, communities, and societies with an effort to maximize access, par ticipation, and supports. Research on inclusion reveals benefits for individuals with disabilities and for typically developing children. As such, to the maximum extent appropriate, children with dis abilities should be educated with children who do not have disabili ties. In general, removal from the regular educational environment should occur only when the nature or severity of the childs dis ability is such that education in regular classes with the use of sup plementary aids and services cannot be achieved satisfactorily, not simply because significant curriculum modifications are needed. Children who are educated in more inclusive settings, regardless of overall developmental level, tend to have higher rates of com munity participation as adults. Behavioral challenges are the most limiting factor in terms of full inclusion, both in school and within the community, emphasizing the importance of implementing early and consistent behavior management strategies. Beyond education services, families of children with ID often are eligible for federal or state provided social
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services. All states offer developmental disabilities programs that provide home and Table 56.11 Severity of Intellectual Disability and Adult Age Functioning LEVEL SUPPORT LEVEL FUNCTIONAL AGE EQUIVALENT AS ADULT ADULT ADAPTATION Mild Intermittent 9 11 yr Reads at fourth to fifth grade level; simple multiplication and division; can write a simple list or letter; completes job application; basic independent job skills (arrive on time, stay at task, interact with coworkers); uses public transportation, might qualify for drivers license; keeps house, cooks using recipes; challenges with planning and money management; at risk of being manipulated by others; may need support for making decisions in healthcare, shopping, finances, and raising a family. Moderate Limited 6 8 yr Sight word reading; copies information (e.g., address from card to job application); matches written number to number of items; recognizes time on clock; communicates; some independence in self care; housekeeping with supervision or cue cards; meal preparation, can follow picture recipe cards; job skills learned with much repetition; employment in a supported environment; use of public transportation with some supervision; successful friendships attained, but social judgment and life decisions require support. Severe Extensive 3 5 yr Little understanding of written language or number, time, and money concepts; needs extensive supports for problem solving; trainable in some basic activities of daily living, but needs some level of continuous support and supervision for most activities; might communicate wants and needs with use of basic words, phrases, gestures, or with the use of augmentative and alternative communication techniques; trainable in some basic activities of daily living. Profound Pervasive 3 yr Dependent for self care, continence, communication needs with supports required for all activities of everyday living; co occurring physical and sensory limitations are common; may use objects in a goal directed fashion for recreation or self care; limited understanding of symbolic communication, but may understand some gestures and emotional cues; uses nonverbal expressions; might need complete custodial or nursing care. Data from World Health Organization. International Statistical Classification of Diseases and Related Health Problems, 10th revision. Geneva: WHO; 2011 and American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, 5th ed. Washington, DC: American Psychiatric Association. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 56 u Developmental Delay and Intellectual Disability 361 community based services to eligible children and adults, poten tially including in home supports, care coordination services, resi dential living arrangements, vocational and employment support programs, and additional therapeutic options. A variety of Medic aid waiver programs are also offered for children with disabilities within each state. Children with ID who live in low income status households can qualify to receive supplemental security income (SSI), but many of these families do not receive the benefits to which they are eligible. Leisure and Recreational Activities The childs social and recreational needs should be addressed. Although young children with ID
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are generally included in play activities with children who have typical development, adolescents with ID often do not have opportunities for enriching social inter actions. Community participation among adults with ID is much lower than that of the typical population even though these indi viduals tend to have the same preferences and wishes for leisure activities as their nondisabled peers. Individuals with ID experience high rates of marginalization, especially from involvement in for mal recreational programs, often because of insufficient resources to accommodate participation, difficulties with expenses and trans portation, and so forth. To reduce isolation, ideas for inclusion in leisure activities should be explored with families, including church group involvement, Boy and Girl Scout chapters, 4H clubs, local park district programs, and musical opportunities like choir and instrumental lessons. Participation in sports should be encouraged (even if the child is not competitive) because it offers many ben efits, including weight management, development of physical coor dination, maintenance of cardiovascular fitness, and improvement of self image. Inclusion in class trips, dances, dating, and other social events should be encouraged. International programs such as Special Olympics and Best Buddies International seek to enhance inclusion and visibility of individuals with disabilities and can be a valuable resource. Family Counseling Many families adapt well to having a child with ID, but some have emotional or social difficulties. The risks of parental depression and child abuse and neglect are higher in this group of children than in the general population. The factors associated with good family coping and parenting skills include stability of the marriage, good parental self esteem, limited number of siblings, higher socioeconomic sta tus, lower degree of disability or associated impairments (especially behavioral), parents appropriate expectations and acceptance of the diagnosis, supportive extended family members, and availability of community programs and respite care services. In families in whom the emotional burden of having a child with ID is great, family coun seling, parent support groups, sibling support groups and camps, respite care, and home health services should be an integral part of the treatment plan. Transition to Adulthood The transition to adulthood can present a stressful and chaotic time for the adolescent with ID and their family (see Chapter 152). A successful transition correlates with better quality of life but requires significant advanced planning. The transition process for those with ID extends beyond medical care and needs to include education and employment, health and well being, finances and independence, and social and community life. Specific issues include: u Decision making (supported decision making, guardianship, power of attorney) u Accessing and securing social benefits for which the person is eligi ble (e.g., SSI, Medicaid) u The choice of living arrangements and necessary supports (inde pendent living, shared living arrangements, or living with parents; community integrated living arrangements; group homes) u Estate planning for the parents (ABLE accounts, special needs trust) u Postsecondary training (vocational choices, postsecondary educa tion pacer.org) u Community participation and involvement in leisure activities (e.g., community service and volunteering
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activities, religious groups, Special Olympics, Best Buddies, local clubs) Successful transition is difficult to achieve because of policies, sys tems, and services that are not comprehensive or coordinated. In moving from child to adult care, families tend to find that services are less readily available, more fragmented, and more difficult to navigate across multiple agencies and jurisdictions. Transition planning is a required element of the IEP process by age 16 years, and options for continued education or entry into the workforce after high school should be thoroughly considered, with the greater goal of ultimate community based employment. Postsecond ary education possibilities might involve community college or voca tional training. In 2008, the U.S. Higher Education Opportunity Act (HEOA) granted students with ID access to federal financial aid to attend colleges with Comprehensive Transition Programs (CTPs), which are designed for postsecondary students with ID to continue academic, career and technical, and independent living instruction to prepare for employment. As of 2019, more than 265 nondegree postsecondary programs for students with ID exist nationwide in the United States. Although employment is a critical element of life adaptation for persons with ID, only 15 are estimated to have jobs, with significant gaps in pay and compensation compared to workers without disabil ity. Employment selection should be customized to the individuals interests and abilities. Options may include participation in com petitive employment, supported employment, high schooltowork transition programs, job coaching programs, and consumer directed voucher programs. Self Advocacy The self advocacy movement represents an important effort by per sons with ID and other disabilities to advocate for maximal autonomy and self determination in all aspects of life. This movement is a part of the greater disabilities rights movement and represents a resistance to historical systemic injustices experienced by individuals with ID, including neglect, abuse, nonautonomy, marginalization, incarcera tion, sterilization, and isolation. Self advocacy stresses that individuals with ID should be able to speak for themselves, should be involved maximally in decision making, should be treated as equal and fully included in society, and should be given as much control over their own self direction as possible. This movement emphasizes the tenet of nothing about us without us and has led to nationwide changes in terms of policy and medical and legal nomenclature. Above all, the self advocacy movement has sought to redefine the approach to dis ability, moving toward a social model of acceptance, equality, accom modation, and inclusion, putting the onus on society to change its attitudes and practices rather than calling on the individual with ID to change. OUTCOMES In children with severe ID or ID requiring significant supports, the prognosis is often evident by early childhood. Mild ID might not always be a lifelong disorder. Children might meet criteria for GDD at an early age, but later the disability can evolve into a more specific developmental disorder (language disorder, autism, ADHD, specific learning disability, or borderline intelligence). Others with a diagno sis of mild ID during their school years may develop
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sufficient adap tive behavior skills that they no longer fit the diagnosis as adolescents or young adults, or the effects of maturation and plasticity may result in children moving from one diagnostic category to another (from Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 362 Part IV u Learning and Developmental Disorders moderate to mild ID). Conversely, some children who have a diagnosis of a specific learning disability or communication disorder might not maintain their rate of cognitive growth and may fall into the range of ID over time. The apparent higher prevalence of ID in low and middle income countries is of concern, given the limitations in available resources. Community based rehabilitation (CBR) is an effort promoted by the World Health Organization (WHO) over the past 4 decades as a means of making use of existing community resources for persons with disabilities in low income countries, with the goal of increas ing inclusion and participation within the community. CBR is now being implemented in 90 countries, although the efficacy of such programs has not been established. The long term outcome of persons with ID depends on the underly ing cause; degree of cognitive and adaptive deficits; presence of associ ated medical, developmental, and behavioral impairments; capabilities of the families and schools; and availability of community supports, services, and training provided to the child and family (see Table 56.10). As adults, many persons with mild ID can gain economic and social independence with functional literacy, but they may need peri odic support or supervision (especially when under social, economic, or health related stress). Most live successfully in the community, either independently or in supervised settings. Many will marry, some will have children, and meaningful and long lasting relationships can be expected. For persons with moderate ID, the goals of education are to enhance adaptive abilities and survival academic and vocational skills, so they are better able to live and function in the adult world (Table 56.11). The concept of supported employment has been very beneficial to these individuals; the person is trained by a coach to do a specific job in the setting where the person is to work, bypass ing the need for a sheltered workshop experience and resulting in successful work adaptation in the community and meaningful inclusion. These persons generally live at home with family or in a supervised setting in the community, such as a community inte grated living arrangement (CILA) where different levels of super vision and support are provided depending on the needs of the individuals. There has been a strong movement away from institu tionalized living, defined as residence in a facility of four or more people who did not choose to live together. As adults, people with severe to profound ID usually require exten sive to pervasive supports (see Table 56.11). These individuals often have associated
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impairments, such as CP, behavioral disorders, epi lepsy, or sensory impairments, that further limit their adaptive func tioning. They can perform simple tasks in supervised settings. Most people with this level of ID can live in the community with appropri ate supports, though some may require a higher level of institutional care that is best provided though smaller community run group home settings. The life expectancy of people with mild ID is similar to the gen eral population, with a mean age at death in the early 70s. However, persons with severe and profound ID have a decreased life expec tancy at all ages, presumably from associated serious neurologic or medical disorders, with a mean age at death in the mid 50s. Given that persons with ID are living longer and have high rates of comor bid health conditions in adulthood (e.g., obesity, hypertension, dia betes), ID is now one of the costliest ICD 10 diagnoses, with an average lifetime cost of 1 2 million dollars per person. Thus the pri orities for pediatric primary care are to improve healthcare delivery systems during childhood; facilitate the transition of care to adult providers; and ensure high quality, integrated, community based services for all persons with ID. Visit Elsevier eBooks at eBooks.Health.Elsevier.com for Bibliography. PRINCIPLES OF CARING FOR CHILDREN WITH COMPLEX GENETIC DISORDERS Down syndrome (trisomy 21) is the most common genetic cause of intellectual disability, with an incidence of 1 in 700 live births in the United States. Many of the principles of care for individuals with Down syndrome generalize to other complex genetic disor ders. Genetic disorders generally affect all cells in the body, and hence tend to be multisystemic disorders. Trisomy 21s multisystem effects require monitoring of all organ systems for potential related issues. Chromosome 21 is the smallest human autosome, which likely accounts for the relatively high fetal survival rate in trisomy 21. The clinical manifestations of other trisomies and aneuploidies are shown in Tables 57.1 and 57.2 and Figs. 57.1, 57.2, and 57.3. Fetuses with other Chapter 57 Down Syndrome and Other Abnormalities of Chromosome Number Mary Pipan Table 57.1 Chromosomal Trisomies (13, 18) and Their Clinical Findings TRISOMY 13 TRISOMY 18 HEAD AND FACE Scalp defects (e.g., cutis aplasia) Microphthalmia, corneal abnormalities Cleft lip and palate in 6080 of cases Microcephaly Microphthalmia Sloping forehead Holoprosencephaly (arrhinencephaly) Capillary hemangiomas Deafness Small and premature appearance Tight palpebral fissures Narrow nose and hypoplastic nasal alae Narrow bifrontal diameter Prominent occiput Micrognathia Cleft lip or palate Microcephaly CHEST Congenital heart disease (e.g., VSD, PDA, ASD) in 80 of cases Thin posterior ribs (missing ribs) Congenital heart disease (e.g., VSD, PDA, ASD) Short sternum, small nipples EXTREMITIES Overlapping of fingers and toes (clinodactyly) Polydactyly Hypoplastic nails, hyperconvex nails Limited hip abduction Clinodactyly and overlapping fingers; index over third, fifth over fourth; closed fist Rocker bottom feet Hypoplastic nails GENERAL Severe developmental delays and prenatal and postnatal growth restriction Renal abnormalities 1year survival 10 Severe developmental delays and prenatal and postnatal growth
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restriction Premature birth, polyhydramnios Inguinal or abdominal hernias 1year survival 10 ASD, Atrial septal defect; PDA, patent ductus arteriosus; VSD, ventricular septal defect. From Behrman RE, Kliegman RM. Nelson Essentials of Pediatrics, 4th ed. Philadelphia: Saunders;2002: 142. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 57 u Down Syndrome and Other Abnormalities of Chromosome Number 363 Table 57.2 Other Rare Aneuploidies and Partial Autosomal Aneuploidies DISORDER KARYOTYPE CLINICAL MANIFESTATIONS Trisomy 8 47,XXXY,8 Growth and mental deficiency are variable. The majority of patients are mosaics. Deep palmar and plantar furrows are characteristic. Joint contractures are present. Trisomy 9 47,XXXY,9 The majority of patients are mosaics. Clinical features include craniofacial (high forehead, microphthalmia, low set malformed ears, bulbous nose) and skeletal (joint contractures) malformations and heart defects (60). Trisomy 16 47,XXXY,16 The most commonly observed autosomal aneuploidy in spontaneous abortion; the recurrence risk is negligible. Tetrasomy 12p 46,XX1246,XX, i(12p) 8 (mosaicism for an isochromosome 12p) Known as Pallister Killian syndrome Sparse anterior scalp hair (more so temporal region), eyebrows, and eyelashes; prominent forehead; chubby cheeks; long philtrum with thin upper lip and cupid bow configuration; polydactyly; streaks of hyperpigmentation and hypopigmentation A B C Fig. 57.1 Several physical manifestations of trisomy 18. A, Typical profile reveals prominent occiput and low set, posteriorly rotated malformed auricles. B, Clenched hand showing typical pattern of overlapping fingers. C, Rocker bottom feet. (Courtesy Kenneth Garver, MD, Pittsburgh, PA.) Fig. 57.2 Trisomy 13 syndrome. Note sloping forehead with variable defect in facial development. (From Jones KL, Jones MC, Del Campo M. Smiths Recognizable Patterns of Human Malformation, 8th ed. Philadelphia: Elsevier; 2022: Fig. 1 A C, p. 16.) Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 364 Part IV u Learning and Developmental Disorders full autosomal trisomies are not always viable, but partial trisomy and quatrosomy (trisomy or quatrisomy of only part of the chromosome) or mosaic trisomy (only part of the cell lines contain the aneuploidy) can be viable. The Down syndrome phenotype can occur as a result of full trisomy 21 (95), partial trisomy 21 (part of the 21st chromosome in tripli cate), mosaic trisomy 21, or translocation. Maternal nondisjunction in meiosis is the most common cause of trisomy 21. Paternal origin accounts for less than 10. Chromosome abnormalities affect not only the product and func tion of that particular group of genes but can have upstream and down stream effects on other gene products in linked pathways. The over 314 triplicate genes in Down syndrome are known to affect the products and metabolic activity of genes from every other chromosome. Pos sible phenotype (condition) gene relationships in trisomy 21 are noted in Figure 57.4. The link between childrens physical health, development,
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and behavior becomes obvious when caring for children with complex genetic disorders. Children with developmental disabilities often cannot adequately communicate the symptoms of illness. Challeng ing behaviors can also interfere with adequate assessment and inter vention. Too often, sources of distress, developmental challenges, and behavioral issues are attributed to the genetic disorder and dismissed by family, medical, and educational caregivers. Provid ing care for genetically complex children requires health and other providers to consider a range of potential differential diagnoses when presented with a change in behavior, a plateau or regression in development, or a new physical complaint. Trisomy 21 affects brain development across the life span, leading to differences in brain anatomy, neurotransmission, and connec tivity that affect processing, glial cell function, infrastructure sup port, energy metabolism, and in adults, the formation of amyloid plaques leading to high risk for early Alzheimer disease. Alterations in brain development and functioning affect learning, behavior, and emotions, leading to an increased incidence of neurobehavioral and psychiatric disorders such as autism spectrum disorders (ASDs), attention deficithyperactivity disorder (ADHD), anxiety disor ders, and depression. It is important for the clinician to understand that children with genetic disorders are genetically more closely related to their bio logic family than they are to other children with similar disorders. Children with Down syndrome will have similar patterns of familial heritability for heritable traits and medical conditions as their bio logic siblings. Individuals with genetic disorders need to be seen as childrenpersons first who happen to have a genetic disorder. Using person first language (child with Down syndrome, not Downs child) helps everyone focus on this principle. CLINICAL CHARACTERISTICS Children with Down syndrome are at increased risk for a variety of congenital anomalies and comorbid medical conditions. Typically, they have a characteristic facial appearance and other physical characteris tics that allow clinical recognition of trisomy 21 in the newborn period (Figs. 57.5 and 57.6 and Table 57.3). The increased risk for a variety of medical conditions continues throughout the life span (Table 57.4). The American Academy of Pediatrics (AAP) has developed Down Syndrome Health Supervi sion Guidelines for clinicians caring for children with trisomy 21 (Table 57.5). Individuals with Down syndrome often have signifi cant communication deficits, which can result in difficulty report ing pain and discomfort; clinicians need to pay attention to the caregivers observation of changes in behavior when evaluating the level of pain or illness. Paying close attention to subtle cues on exam A B C D Fig. 57.3 Trisomy 13. A and B, Note hyperconvex nails and postaxial polydactyly. C, Aplasia cutis congenita over posterior occiput. D, Scrotaliza tion of the phallus. (From Jones KL, Jones MC, Del Campo M. Smiths Recognizable Patterns of Human Malformation, 8th ed. Philadelphia: Elsevier; 2022: Fig. 2, p. 17.) Heart defect CHD 50 AVSD 40 VSD 30 CRELD 1 DSCAM miRNA hsamiR155GATA 1(AMKL) JAK2 (ALL) APP BACE2 PICALM APOE Down syndrome Hsa21 gene Hypertension Gastrointestinal problems 12 HD 260 times DST 33 times IA Alzheimer disease 70 chance
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of AD Leukemia 1020 fold Fig. 57.4 Various conditions associated with Down syndrome with its causative genes. DST, Duodenal stenosis; IA, imperforate anus; HD, Hirschsprung disease; CHD, congenital heart disease; AVSD, atrioven tricular septal defects; VSD, ventricular septal defect; AD, Alzheimer disease. (From Asim A, Kumar A, Muthuswamy S, et al. Down syn drome: An insight of the disease. J Biomed Sci. 2015;22:41, Fig. 1.) Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 57 u Down Syndrome and Other Abnormalities of Chromosome Number 365 D E F A B C Fig. 57.5 Down syndrome in the neonatal period. A, Brushfield spots. B, Loose nuchal skin. C, Wide space between toes 1 and 2. D, Poor tone. E and F, Accentuation of typical face when crying. (From Jones KL, Jones MC, Del Campo M. Smiths Recognizable Patterns of Human Malformation, 8th ed. Philadelphia: Elsevier; 2022: Fig. 3, p. 7.) Fig. 57.6 Appearance of two 2 year old children with trisomy 21. The facial appearance of children with trisomy 21 is often characterized by a low nasal bridge, small nose, small ears, up slanting almond shaped eyes, and epicanthal folds. (Photos courtesy of Childrens Hospital of Philadelphia.) Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 366 Part IV u Learning and Developmental Disorders Table 57.3 Clinical Features of Trisomy 21 in the Neonatal Period CENTRAL NERVOUS SYSTEM Hypotonia Developmental delay Poor Moro reflex CRANIOFACIAL Brachycephaly with flat occiput Flat face Upward slanted palpebral fissures Epicanthal folds Speckled irises (Brushfield spots) Three fontanels Delayed fontanel closure Frontal sinus and midfacial hypoplasia Mild microcephaly Short, hard palate Small nose, flat nasal bridge Protruding tongue, open mouth Small dysplastic ears CARDIOVASCULAR Endocardial cushion defects Ventricular septal defect Atrial septal defect Patent ductus arteriosus Aberrant subclavian artery Pulmonary hypertension MUSCULOSKELETAL Joint hyperflexibility Short neck, redundant skin Short metacarpals and phalanges Short fifth digit with clinodactyly Single transverse palmar creases Wide gap between first and second toes Pelvic dysplasia Short sternum Two sternal manubrium ossification centers GASTROINTESTINAL Duodenal atresia Annular pancreas Tracheoesophageal fistula Hirschsprung disease Imperforate anus Neonatal cholestasis CUTANEOUS Cutis marmorata Halls criteria to aid in diagnosis. Table 57.4 Frequency of Medical Conditions in Trisomy 21 SYSTEM CONDITION ESTIMATED FREQUENCY (IF KNOWN) EYE Cataracts (birthlater) 1.4537 Glaucoma 1 Nystagmus 1830 Strabismus 1934 Refractive errors 80 Astigmatism 6774 Nasolacrimal duct obstruction 1130 ENT Stenotic ear canals 50 Choanal atresia Bifid uvulamucosal cleft 5 Laryngomalacia Middle ear effusions 5090 Adenotonsillar hypertrophy Hearing loss 3778 DENTAL Tooth agenesis 5458 Malocclusion 70 Periodontal disease 100 under 30 years ENDOCRINE Congenital hypothyroidism 1:113 to 1:141 live births Acquired hypothyroidism 1334 Subclinical hypothyroidism 740 Hyperthyroidism 6.5 Type 1 diabetes mellitus 0.31 CARDIAC Congenital heart disease 4454 AV canal defects
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42 (of CHD) VSD 2235 ASD 816 Tetralogy of Fallot 24 Acquired mitral, tricuspid, or aortic regurgitation PDA 57 Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 57 u Down Syndrome and Other Abnormalities of Chromosome Number 367 Table 57.4 Frequency of Medical Conditions in Trisomy 21contd SYSTEM CONDITION ESTIMATED FREQUENCY (IF KNOWN) PULMONARY Pulmonary hypertension 15 Subglottic stenosis 6 Tracheolaryngomalacia 33 (of ENT referred population) Tracheal bronchus Obstructive sleep apnea 50 GASTROINTESTINAL Esophageal atresia 0.50.9 Duodenal malformations 4 Rectoanal malformations 1 Hirschsprung disease 3 Celiac disease 59.8 GERD 1440 Constipation 3049 GENITOURINARY Renalurinary tract findings Up to 25 HEMATOLOGYONCOLOGY Transient myeloproliferative disease (TMD) 510 Acute megakaryoblastic leukemia (AMKL) 1020 with TMD, first 4 years of life Acute lymphocytic leukemia 0.10.2 ORTHOPEDICS Atlantoaxial instability (AAI) 927 Symptomatic AAI 12 Recurrent joint dislocations (shoulder, knee, elbow, thumb) 17 Pes planus 91 Juvenile idiopathic arthritis 1 DERMATOLOGY Alopeciavitiligo 111 Hidradenitis suppurativa 2 Xerosiseczema Seborrheic dermatitis Psoriasis 0.58 NEUROLOGY Infantile spasms 25 Seizure disorders 8 (lifetime) Strokes and moyamoya Autism spectrum disorder 716 Early onset Alzheimer disease 50 50 yr Down syndrome disintegrative disorder 1 ENT, Earnosethroat; AV, atrioventricular; CHD, congenital heart disease; VSD, ventricular septal defect; ASD, atrial septal defect; PDA, patent ductus arteriosus; GERD, gastroesophageal reflux disease. and asking direct questions about specific areas of pain or discom fort can be helpful (e.g., Does your throat hurt? while pointing to or touching their throat). Ophthalmology The red reflex should be evaluated in the newborn period with a thorough ophthalmologic exam in the first 6 months of life and then annually until age 5, then every 2 3 years thereafter. Children with DS are at higher risk for cataracts, glaucoma, nystagmus, strabismus, astigmatism, refractive error, accommodative error, blepharitis, and keratoconus. Visual acuity and visual processing are foundational for development. Ear, Nose, and Throat The pinna and external ear canals are often small with a predisposi tion to cerumen impaction. Middle ear effusion occurs in the major ity of children, starting in infancy, and may require referral to an ear nosethroat (ENT) specialist for better visualization because of ste notic ear canals. Chronic nasal congestion, choanal atresia, adeno tonsillar hypertrophy, laryngotracheomalacia, subglottic stenosis, and laryngeal cleft all can affect feeding and breathing, including con tributing to sleep apnea. Most children with DS require regular ENT follow up. Many children with DS have some degree of hearing loss (HL). Most commonly this is conductive HL associated with middle ear effusion. Smaller numbers have mixed or sensorineural HL. Hearing is founda tional for speech development. Hearing should be screened in the new born period and with audiologic assessment between 6 and 9 months and every 6 months thereafter until an accurate ear specific audiologic evaluation is obtained, then annually. Hearing assessment through auditory brainstem responses (requiring sedation) may be needed if audiologic evaluation is inconclusive. Lack of parental
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concern about hearing should not preclude obtaining audiologic assessment. Aggres sive treatment of otitis media and middle ear effusion reduces the fre quency of hearing loss. Dental Children with DS often have delayed tooth eruption, malformed teeth, microdontia, permanent tooth agenesis, tooth impaction, malocclusion, and supernumerary teeth. Periodontal disease is Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 368 Part IV u Learning and Developmental Disorders Table 57.5 Summary of Down SyndromeSpecific Care Pre natal Action Birth up to 1 mo 1 mo up to 1 yr 1 yr up to 5 yr 5 yr up to 12 yr 12 yr up to 21 yr From Bull MJ, Trotter T, Santoro SL, et al. Health supervision for children and adolescents with Down syndrome. Pediatrics. 2022;149(5):e2022057010. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 57 u Down Syndrome and Other Abnormalities of Chromosome Number 369 seen in the majority of individuals with DS. Starting oral health pre ventive programs young, close supervision and support of dental hygiene and chemical adjuvants improve outcomes. Children with DS should first see a pediatric dentist at age 1 year and follow up at least every 6 months. For children who do not tolerate dental examinations or procedures, sedated examinations may be neces sary, preferably in a hospital with anesthesiologists familiar with caring for patients with DS. Endocrine Children with DS are at risk for congenital and acquired hypothy roidism (HT) and hyperthyroidism (Graves disease GD). Thy roid testing should be done at birth as part of newborn screening. Acquired HT and GD are autoimmune disorders with elevated thyroid antibodies. Thyroid stimulating hormone (TSH) testing can detect both HT and hyperthyroidism and should be checked by 6 months, at 1 year, and then annually thereafter. Most cases of thyroid disorders are asymptomatic and would be missed without screening. Compensated HT refers to mild elevations in TSH with normal T4, requiring continued monitoring. Low TSH can indi cate Graves disease. Children with DS who have GD can develop HT, and those with HT can develop GD. Thyroid disorder should be considered as part of the differential diagnoses with mood or behavior changes, slowing of growth, exophthalmos, high blood pressure, or tachycardia. Type 1 diabetes mellitus (DM) is more common in children with DS. Screening for type 2 DM, especially in obese individuals, should follow similar guidelines to the typically developing (TD) population. Cardiac Congenital heart disease (CHD) affects about half of all children with DS, including atrioventricular (AV) canal defects, atrial septal defect (ASD), ventricular septal defect (VSD), tetralogy of Fallot (TOF), patent ductus arteriosus (PDA), and patent foramen ovale (PFO). All children with DS should have an infant echocardiogram even with a normal
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physical examination. Cardiology follow up will be based on echocardiogram findings. Signs of heart failure such as failure to thrive, tachypnea, easy fatigue, or sweating with feeds require expedited referral back to cardiology. Pulmonary hypertension can also occur in children with DS related to congeni tal heart defects or to respiratory illness. Later in adolescence and adulthood, clinicians should be aware of the increased risk for val vular heart disease and endocarditis. Pulmonary Respiratory infections are the most common cause for hospital admission of children with DS without CHD and are a common cause of mortality in children with CHD. Respiratory compromise may present with subtle signs of respiratory distress such as tachy pnea, intercostal retraction, shortness of breath, and easy fatigue with exertion. The lack of overt distress may lead clinicians to underestimate the level of respiratory compromise. Both anatomy and immunodeficiency associated with DS can lead to increased risk for upper and lower respiratory infections. Macro and micro pulmonary structural anomalies have been reported. Gastroesopha geal reflux disease, swallowing dysfunction, and upper airway dif ferences (including transesophageal TE fistula) increase the risk of aspiration. Sleep The estimated prevalence of obstructive sleep apnea (OSA) ranges from 31 to 79, and onset occurs from infancy through adult hood. A sleep study before the age of 4 years is recommended. Clinicians should consider ordering a sleep study at any age, with chronic signs of respiratory compromise when awake or asleep or daytime symptoms of nonrestorative sleep. There is some evidence that OSA causes difficulties in cognitive, behavioral, and adaptive functioning in children with DS. Obesity increases the risks for OSA in many children with DS. Neurology Children with DS ages 6 18 months are at increased risk for infan tile spasms (IS). The outcome is often better with treatment than the nonDS population with ID but is variable, ranging from no obvious sequelae to ongoing seizure disorders, ASD, and more severe intellec tual disability. In addition to the classic signs of IS, change in mental status in an infant or toddler or a plateau or regression in development should lead to prompt neurologic evaluation, including an electroen cephalogram (EEG). Children with trisomy 21 are at increased risk for other seizure disorders. There is an increased risk for strokes possibly related to CHD, vascular malformations (including moyamoya syn drome), and other risk factors. Gastrointestinal Most children with DS have structural or functional gastrointesti nal (GI) comorbidities, many of which can affect individuals across the life span. There is evidence of abnormalities in enteric nerves affecting microanatomy and nerve function. Congenital anomalies include esophageal atresia, TE fistula and duodenal atresia, steno sis, and webs, Hirschsprung disease, and anorectal malformations. Constipation and gastroesophageal reflux disease (GERD) are fre quent causes of irritability, GI discomfort, feeding issues, toileting refusal, and incontinence. There appears to be a strong association between GERD, pneumonia, and OSA. Children with DS are also at higher risk of celiac disease, which can cause GI, nutritional, and behavioral issues. The AAP guidelines
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do not recommend routine celiac screening, but rather to maintain a high index of suspicion with GI complaints, growth faltering, or behavioral concerns. Many others, however, have performed routine screening because many patients with DS who have celiac disease are asymptomatic; there may be a lag of 2 3 years before symptoms appear. NutritionObesity In infancy and early childhood, dysphagia, GI conditions, cardiac, and respiratory complications may cause failure to thrive. Weight faltering can continue for older children because of the same issues but may be more intermittent. Because of the high rates of dyspha gia in infants with DS, video swallow studies should be considered when there is any sign of weight faltering, aspiration, feeding dif ficulties, or recurrent respiratory infections. Thickened formulas, low flow bottlesnipples, or slower paced feeding may be required. Nasogastric (NG) or gastric tube (GT) supplementation to assure adequate nutrition may be needed. Many babies with DS can suc cessfully breastfeed, and clinicians need to be encouraging but watchful for growth faltering. Obesity becomes more prominent in early childhood and extend ing into adulthood. In schoolage children with DS, those at 50 or greater on DSspecific BMI charts are in the obese range. Thus to gauge the level of overweight for children with DS, the Centers for Disease Control and Prevention (CDC) curves for BMI should be used. When children with DS gain more autonomy in feeding, over eating can become a problem. Many do not appear to satiate and will continue to eat as long as food is presented or will seek food. Caregiv ers therefore cannot rely on the childs satiety to determine caloric sufficiency. Decreased basal metabolic rates (reduced caloric needs) and lower physical activity can also contribute to obesity. Anticipa tory guidance regarding healthy nutritional practices, meal and snack limits, and active lifestyle choices should be part of well child visits from a young age. Genitourinary Renal and urinary tract abnormalities, including ureteropel vic junction obstruction, vesicoureteral reflux, renal hypoplasia, obstructive uropathy and posterior urethral valves, hypospadias, Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 370 Part IV u Learning and Developmental Disorders asymptomatic renal pelvic dilatation, kidney ectopia, proteinuria and hematuria, immunoglobulin A (IgA) nephropathy, and focal segmental glomerulosclerosis, occur more frequently than in the general population. There are no current guidelines for regular sur veillance, but clinicians need to maintain a high index of suspicion. Sexuality and Reproductive Health Males and females with DS undergo puberty at similar ages to peers. In males, after puberty, testicular volume decreases and gonadal dysfunc tion worsens with age. Males are infertile, with few exceptions. Females with DS are fertile, having a 33 chance of having a child with DS. Menstrual problems, including irregular periods, and premenstrual irritability are common reasons for use of oral contraceptives. Most females manage menstrual periods well, but there may be difficulties
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with hygiene. Menopause tends to occur early. Individuals with DS are at increased risk for sexual abuse, and care givers should discuss appropriate and inappropriate contact and rela tionships from an early age. Sexuality education should be included in their educational curriculum. Clinicians should discuss sexuality, birth control, and reproductive issues at health maintenance visits. Table 57.6 Neurodevelopmental, Neurobehavioral, and Psychiatric Characteristics of Trisomy 21 MOTOR SKILLS Gross motor skills 0 24 mo: Mild delays initially which widen with age At 2 years 25 walking Oromotor Dysphagia 0 6 mo: 50 Self feeding delays: 70 Fine motor skill Early skills delays: 75 Bimanual skill delays: 100 SPEECH AND LANGUAGE Intelligibility Frequently unintelligible (parent report): 5 21 yr: 5457 Motor speech impairment: Delay: 27 Articulation: 60 Apraxia: 33 Dysfluency: Stuttering: 1045 Cluttering (abnormally rapid or irregular pace or both): 80 Language Receptive: Similar to mental agematched controls Expressive: More delayed relative to mental agematched controls Syntax: More impaired than expressive vocabulary Pragmatics: Same variety of language functions as mental agematched peers; may be less likely to ask for clarification SOCIAL AND EMOTIONAL DEVELOPMENT High sociability Joint attention compared with mental agematched peers Strong imitation skills Pro social empathetic responses to others in distress Underexpression of emotional distress Less frequent and shorter social referencing Reduced ability to read facial expressions More restricted repetitive behaviors and interests Average social motivation but lower social cognition COGNITION Intellectual disability: Mild: 25 Moderate: 50 Severe: 25 Decline in IQ throughout childhood (slowing in developmental progress relative to same age peers) Strengths: Implicit memory, visual spatial sequencing, visual spatial construction, and nonverbal memory Weaknesses: Working memory capacity, explicit memory, verbal processing, auditory short term memory, complex visual spatial skills, executive functioning Oppositional behaviors 70 Aggression 415 Self injurious behavior 18 Autism spectrum disorders 1520 ADHD 1440 Anxiety disorders 1022 Obsessive compulsive disorders 0.54.5 Depression 511 CatatoniaDown syndrome disintegrative disorder Multiple case series and case reports IQ, Intelligence quotient; ADHD, attention deficithyperactivity disorder. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 57 u Down Syndrome and Other Abnormalities of Chromosome Number 371 Hematology Oncology AAP guidelines recommend a complete blood cell count (CBC) with differential for all newborns with DS. Neonates with DS com monly have hematologic abnormalities, including peripheral blasts, neutrophilia, thrombocytopenia, or polycythemia. Five to ten per cent of neonates with DS have transient myeloproliferative disor der (TMD) (also called transient abnormal myelopoiesis TAM), which is associated with pathologic variants in GATA1. Typically, this resolves spontaneously within the first 1 3 months of life, but 1020 will develop acute megakaryocytic leukemia (AMKL) in the first 4 years of life. AMKL is sensitive to treatment in most cases and has a good prognosis. Children with DS are 20 times more likely to get acute lymphoblas tic leukemia (ALL) (1 in 900 1,000) than the typical population, which is associated with
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pathologic variants in JAK2. Treatment trials show lower response rates, higher recurrence rate, and higher treatment related mortality. Annual hemoglobin screening for anemia is recommended through out childhood with additional testing for ferritin and C reactive protein (CRP) when iron deficiency is suspected. The incidence of anemia in DS may be similar or increased compared with the general population. Other common CBC findings include macrocytosis, low white blood cell (WBC) count, and polycythemia, the clinical significance of which is unknown. ImmunologyAllergy Individuals with DS are more susceptible to infections because of mild to moderate T and B cell lymphopenia, with a decrease in naive lym phocytes, impaired mitogen induced T cell proliferation, reduced spe cific antibody responses to immunizations, and defects of neutrophil chemotaxis. Nonimmunologic anatomic factors also contribute to the increased risk of respiratory infections. Children with DS with signifi cant numbers of serious infections or difficulty clearing infections need further immunologic evaluation. Autoimmune disorders are also more common, including thyroid disorders, celiac disease, alopecia areata, vitiligo, type 1 DM, juvenile idiopathic arthritis, and systemic lupus erythematosus. Musculoskeletal Individuals with DS have short stature across the life span and stop growing sooner than typical peers, the mechanism of which is unclear. Growth hormone is rarely deficient. Ligamentous laxity is common, especially in the ankles and feet. Inflammatory arthritis is underrecognized, and scoliosis is more common. Joint instabil ity is most apparent in the neck (atlantoaxial instability AAI), hips, and knees. Joint pain and impaired mobility can contribute to motor skills deficits, impede independence, and add to behavioral difficulties. Radiographic screening for AAI is not recommended because flex ionextension neck x rays are not predictive for future neurologic risk. Signs and symptoms of AAI occur because of compression of the spinal cord from slippage of the C1 or C2 vertebrae, which can occur after an injury or anesthesia but can also be seen spontaneously. Neck pain, stiffness, andor myelopathic signs and symptoms (e.g., change in gait, bowel, or bladder pattern or weakness) should prompt refer ral to orthopedics or neurosurgery. Universal neck precautions are recommended for all children with DS, assuming that all are at risk for injury from AAI, including limited participation in any activities that would be associated with forcible neck movement such as contact sports, diving, and universal cervical precautions with intubation pro ceduressurgery. Children with DS should be secured in rear facing car seats until 40 pounds and may need harness style car restraints over 40 pounds. Hip instability resulting in recurrent (often painless and voluntary) hip dislocation and patellar instability can impair ambulation and may require surgical interventions. Dermatology Although causing minor morbidity, dermatologic problems can be highly distressing to patients and families due to appearance (e.g., alo pecia), discomfort (e.g., eczema, hidradenitis), or intractability (e.g., onychomycosis). Common conditions include folliculitis, hidradenitis suppurativa, eczematous and seborrheic dermatitis, autoimmune alo pecia and vitiligo, fungal infections including tinea pedis and onycho mycosis, angular cheilitis, and hyperkeratosis. DEVELOPMENTAL AND BEHAVIORAL CHARACTERISTICS Development and behavior concerns are almost universal.
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Some concerns are easily explained and remediated and are responsive to appropriate therapeutic or behavioral interventions, but others may indicate an underlying neurobehavioral disorder such as autism, ADHD, depression, or anxiety (Table 57.6). Thinking through the cat egories that follow will help clinicians understand this complexity and direct families to appropriate resources. Motor Skills Children with DS often have marked delays in motor skills in early development related to hypotonia, ligamentous laxity, and lack of coordination. Acquisition of early gross motor skills is foundational for pos tural control, feeding, visual motor development, socialization, and communication. Without stimulation and support, infants with DS may persist in lax postural control, further adding to motor delays. Through toddler and childhood many gradually improve but have persistent deficits in motor control and coordination and more dif ficulty with speed and complex postural changes, as well as persis tent hypotonia. Physical therapy in the first years of life concentrates on core strengthening and ensuring acquisition of adaptive motor planning that supports effective ambulation. Gait abnormalities and persistent low core strength often require ongoing physical therapy. Developing physical literacy in recreational fitness activities, such as swimming, and community sports can also support health and well being in school age and adult years. Oromotor skills are often delayed, with dysphagia in half of infants, requiring feeding therapy, thickening of formula, low flow nipples, pacing between swallows, and sometimes supplemental enteral feed ing. Feeding therapy helps young children learn to handle food boluses, chew, and drink from a cup. Fine motor skills are also delayed, although they seem to be acquired in the same sequence as typically developing peers, but with a wider age range of acquisition. Most unaffected children are able to write their name between 60 and 72 months, but in children with DS, this usually occurs between 120 and 216 months. Occupational therapy often helps remediate or compensate for motor difficulties interfering with independence in activities of daily living. Speech and Language Skills Individuals with DS often have difficulty speaking clearly enough to be readily comprehensible to listeners across the life span resulting in communication breakdowns, which can be frustrating to both parties. Typical children are 90100 intelligible by age 4 years. In individuals with DS over 50 of parents reported frequent dif ficulties in intelligibility over the age of 5 years into adulthood, and almost all qualify for a diagnosis of a motor speech disorder. Differ ences in voice quality, articulation, phonology, fluency, prosody, and motor coordination (apraxia) all contribute to making speech hard to understand (see Chapter 53). The complexity of speech impairments in children with DS requires speech therapy evaluation with targeted interventions for each individual. Children with DS relative to children matched for nonverbal skills show similar abilities in receptive vocabulary but impairments in expressive vocabulary, syntax, grammar, and verbal short term Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024.
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Elsevier Inc. All rights reserved. 372 Part IV u Learning and Developmental Disorders memory indicative of a specific language impairment (SLI). The frequency of such impairments requires comprehensive language assessment for all children with DS. The language impairment may be associated with decreased ability to express thoughts and feelings verbally and use of fewer words in answer to questions or to carry on a conversation. Misunderstandings may occur if the individual refers to past events in the present tense or thinks that something described as a future event will happen immediately. Verbal short term memory deficits affect comprehension of more complex language (e.g., mul tistep instructions, complex sentences, conversation, and narrative) and reading comprehension. Visual, contextual, and multisensory supports incorporated into both receptive and expressive language can be helpful. Speech and language intervention has been shown to be effective, especially when of higher intensity; focused on individual needs and targeted skills; and when taking into account the individuals age, interests, and motivators. Use of applied behavior analysis to teach communication skills improves outcomes. Incorporating interventions across contexts (classroom, home, and community settings) and into pragmatic language situations outside of structured learning settings (e.g., peer interaction, conversation) supports generalization of skills learned in therapy. For some individuals with DS, speech and lan guage intervention will be required through school and possibly into adulthood. Social and Emotional Development Social and emotional development occurs as a complex transactional process between the child and their social partners. Children with developmental delays will likely also have delays in their social inter actions, social communication, and play. Children with DS often have a strong orientation toward sociability. From early infancy, mutual gaze in babies with DS emerges more slowly but once established tends to last longer, with sometimes strong preferences for looking at people as opposed to toys and other objects. Development of joint attention is commensurate with developmental age matched peers and may be a relative strength. Strong imitation skills are noted in children with DS. Children with DS show stronger pro social empa thetic responses to others distress, but their own expression of dis tress tends to be dampened (often described as high pain tolerance or, in older children, a perceived reluctance to acknowledge feelings of distress). There are relative weaknesses in social development, which can help explain some of the social difficulties caregivers encounter. Children with DS have been shown to socially reference less frequently, with shorter glances toward others, and some have more difficulty inter preting the facial expressions of others. Older children with DS have more restricted repetitive behaviors and interests, including rigidity and insistence on sameness. Despite typical social motivation, they may have difficulties with social cognition and difficulty gaining and maintaining friendships. Having friends has been associated with improved quality of life in children with DS. Most adolescents are happy with their level of friendships, but friends may include helpers and adult companions. Leisure time is often spent at home with family or by themselves, and socializing with same
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age peer friends occurs predominantly in the context of common educational or community activities. Building healthy sustained friendships with both TD peers and those with developmental disabilities often requires active ongo ing caregiver and community support to prevent social isolation and loneliness as children transition to adulthood. Cognition Individuals with DS have varied degrees of intellectual and learn ing disabilities. Intelligence quotient (IQ) scores of adults with DS are mostly in the 40s 60s, and tests of adaptive functioning typically have standard scores in the low 50s. In children with DS, IQ scores tend to decline with age because progress is slower than same age peers, and deficits are more marked in higher level thinking. Thus the gap between children with DS and same age peers widens with age. An actual plateau in functioning before mid adolescence or a decline at any age is not typical and should prompt thorough etiologic evaluation. IQ scores are of limited value for intervention planning, as they provide limited information about relative strengths and weak nesses. Children with DS often have relative strengths in areas of imitation, implicit memory, visual spatial sequencing, visual spatial construction, and nonverbal memory. Relative weaknesses tend to occur in working memory capacity, explicit memory, verbal pro cessing, auditory short term memory, more complex visual spatial skills (mental rotation, closure, wayfinding), and executive func tioning (see Chapter 49). Recognizing a childs individual learning profile and building on strengths while supporting weaknesses will help caregivers, teachers, and therapists work together to teach chil dren effectively to their potential. Childrens reading skills are generally commensurate with their nonverbal mental age. Many children with DS can learn to read, some phonologically, some orthographically. Reading comprehen sion largely relies on language comprehension skills and is often more difficult. Mathematics is much more difficult because of weak working mem ory, language deficits, and fine motor skills. Math interventions gener ally include direct instruction, modeling, guided and repeated practice, and use of concrete materials. Neurobehavioral Challenges and Disorders Autism Spectrum Disorder Due to the sociability associated with children with DS, ASDs have been underrecognized in the past but are estimated to occur in 1520 of children with DS. Studies also have shown that autism symptoms are not attributable to the degree of developmental disability and that individuals with DS and ASD are distinct from those with DS alone. Children with DS who show high levels of repetitive behavior, maladap tive behaviors (e.g., aggression, self injury, destructive behaviors), social isolation, or difficulty with reciprocal social interaction should be referred for further evaluation, even when overtly sociable. Children with ASD require specialized behavioral and educational interventions with an emphasis on functional communication, social and play skills develop ment, and sensory based supports (see Chapter 58). ADHD The reported incidence of ADHD in children with DS varies greatly, from 14 to 44. Inattention, impulsivity, and hyperactivity, the core symptoms of ADHD, are nonspecific, and it can be difficult to differentiate all the factors contributing to these symptoms in children
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with DS (see Chapter 50). From a clinical perspective, the diagnosis of ADHD relies on reports of ADHD symptoms from two different settings (usually parent and teacher) and dysfunction caused by the ADHD symptoms in areas such as learning, social ization, and safety. Medication use in ADHD has been shown to be effective in children with DS, but the response rates are lower than in typical peers with ADHD. Further, there are higher rates of significant side effects, with some children showing decline in behavior and cognitive performance on medication. Aggression and Self Injurious Behaviors Aggressive behavior is more common in children with many genetic disorders, including DS. The estimated incidence in DS is 415, which is higher than the general population but less than many other genetic syndromes. Aggression disproportionately affects quality of life for the individual and family members and may result in the use of medications and more restrictive educational placements. These behav iors occur more often in males and in individuals with ASD, ADHD, or poor communication skills. Self injurious behavior (SIB) occurs in Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 58 u Autism Spectrum Disorder 373 18. Individuals with DS who engage in SIB are likely to have lower cognitive and communication ability (may be nonverbal), more repeti tive behaviors, higher levels of activity and impulsivity, and fewer social interactions. Assessment of aggression or SIB should include a func tional behavioral analysis (FBA) along with overall skills assessment with emphasis on communication. New onset or escalation of aggres sion or SIB should also include careful assessment for potential sources of pain or discomfort that may exacerbate these behaviors. Behavioral interventions designed based on the results of the FBA should be the initial intervention. Medications may be needed to address symptoms of ADHD, irritability, mood, or anxiety. Oppositional Behaviors Disobedience and stubbornness are common. In some cases, this behavior may relate, at least in part, to differences in cognitive processing. Children with DS have difficulty shifting attention or disengaging from activities. They often desire sameness and resist changes to routine or to the way they think things should be done. Difficulties with language comprehension or frustration with a task or trying to express oneself may result in behaviors that are seen as oppositional. When combined with difficulty problem solving, low frustration tolerance, and emotional dysregulation, disruptive or sometimes verbally or physically aggressive behaviors may result. Before diagnosing a child as having oppositional defiant disorder (see Chapter 42), clinicians should try to understand potential com prehension or skill deficits that may be contributing to the behav ior. If the child has difficulty with transitions, interventions to help them shift activities more easily such as transition routines, warn ings, or countdowns may be most helpful. Visual schedules can also be helpful to prepare the child for what is next, as
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can providing some additional time for the transition. Simplifying language can help avert communication frustration. Anxiety There is an increased prevalence of anxiety disorder in children with DS compared with typical peers. Generally, anxiety disorders are diagnosed based on verbal descriptions of fear or worry and the impact of the fear or worrying on functioning or individual dis tress. Whereas some individuals with DS have the language skills to describe these experiences, others do not. Clinicians often need to rely on the history from caregivers and contextual cues. Behav ioral reactions to anxiety can result in flight or fight responses. Thus anxiety could manifest with aggressive or escapeavoidance behaviors. Cognitive behavioral therapy or exposure therapies can be helpful, and medication management is sometimes needed when anxiety is overwhelming or affects sleep or daytime function ing. Evidence for effectiveness of intervention in DS specifically is sparse. Obsessive Compulsive or Perseverative Behaviors Children and adults with DS often need specific things to be a certain way or may have repetitive patterns of behavior that can seem obses sive or compulsive. They may spend many minutes arranging pillows on their bed, need all doors in the house to be shut, make long lists, or perseveratively ask about upcoming events. These behaviors can be associated with anxiety, and the possibility of increased anxiety should be investigated if there are sudden increases in intensity or frequency of these behaviors. Depression The prevalence of depression in DS ranges from 4 to 11, with most studies being done in adults. This may be an underestimation, as depression in individuals with intellectual disability can be dif ficult to diagnose because of limited abilities to self report internal mood states. Behavioral symptoms can include anxiety, increases in obsessive compulsive behaviors, depressed affect, crying for no reason, lack of emotion, social isolation, anhedonia, irritability with increases in outbursts or aggression, sleep disturbance, psychomo tor retardation, low self esteem, catatonia, and psychosis. Clinicians need to consider potential contributing factors, including medical factors, recent life stressors, trauma, and family history. Anecdot ally, interventions that involve reengagement in previously enjoyed activities and treatment with selective serotonin reuptake inhibitors (SSRIs) can be effective. Catatonia (Also Known as Down Syndrome Disintegrative Disorder or Down Syndrome Regression Disorder) Older children and young adults can experience a sudden regression in communication, socialization, and daily living skills associated with psychomotor retardation, negative mood or mood lability, refusal to participate in activities, social withdrawal, and insomnia with signs and symptoms of catatonia on the Bush Frances Catatonia Scale (see Chapter 47.3). Patients should undergo a medical evaluation for mental status change. Contributing etiologic factors include stressful events, depression, anxiety, or high physiologic stress. Treatment con sists of addressing the underlying suspected cause and may include a trial of Ativan and then electroconvulsive therapy (ECT) if Ativan is unsuccessful. Visit Elsevier eBooks at eBooks.Health.Elsevier.com for Bibliography. DEFINITION Autism spectrum disorder (ASD) is a neurobiologic disorder with onset in early childhood. The key features are impairment in social communication and social
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interaction and restricted and repetitive behaviors. The presentation of ASD can vary significantly from one individual to another, as well as over the course of development for a particular child. There is currently no diagnostic biomarker for ASD. Accurate diagnosis therefore requires careful review of the history and direct observation of the childs behavior. DIAGNOSTIC CRITERIA AND SYMPTOMS The diagnostic criteria in the Diagnostic and Statistical Manual, Fifth Edition (DSM 5) focus on symptoms in two primary domains: (1) social communication and social interaction and (2) restricted inter ests and repetitive behaviors (Table 58.1). To meet criteria for ASD, the symptoms need to have been present since the early developmen tal period, significantly affect functioning, and not be better explained by the diagnosis of intellectual disability (ID) or global developmental delay (GDD; Chapter 56). Table 58.2 provides associated features not included in the DSM 5 criteria. Symptoms can present in infancy, with reduced response to name and unusual use of objects being strong predictors for risk of ASD. However, symptoms before age 12 months are not as reliably predic tive of later diagnosis. Individuals with milder severity may not present Chapter 58 Autism Spectrum Disorder Carolyn F. Bridgemohan and Carol C. Weitzman Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 374 Part IV u Learning and Developmental Disorders Table 58.2 Associated Features of Autism Not in DSM 5 Criteria Atypical language development and abilities Age 6 yr: frequently disordered and delayed in comprehension; two thirds have difficulty with expressive phonology and grammar Age 6 yr: disordered pragmatics, semantics, and morphology, with relatively intact articulation and syntax (i.e., early difficulties are resolved) Motor abnormalities: motor delay; hypotonia; catatonia; deficits in coordination, movement preparation and planning, praxis, gait, and balance For version with full references, see American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Washington DC: American Psychiatric Association; 2013. Adapted from Lai MC, Lombardo MV, Baron Cohen S. Autism. Lancet. 2014;383:896910. Table 58.1 DSM 5 Diagnostic Criteria for Autism Spectrum Disorder A. Persistent deficits in social communication and social interaction across multiple contexts, as manifested by the following, currently or by history: 1. Deficits in social emotional reciprocity. 2. Deficits in nonverbal communicative behaviors used for social interaction. 3. Deficits in developing, maintaining, and understanding relationships. B. Restricted, repetitive patterns of behavior, interests, or activities, as manifested by at least two of the following, currently or by history: 1. Stereotyped or repetitive motor movements, use of objects, or speech. 2. Insistence on sameness, inflexible adherence to routines, or ritualized patterns of verbal or nonverbal behavior. 3. Highly restricted, fixated interests that are abnormal in intensity or focus. 4. Hyperreactivity or hyporeactivity to sensory input or unusual interest in sensory aspects of the environment. C. Symptoms must be present in the early developmental period (may not become fully manifest until social demands
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exceed limited capacities, or may be masked by learned strategies in later life). D. Symptoms cause clinically significant impairment in social, occupational, or other important areas of current functioning. E. These disturbances are not better explained by intellectual disability (intellectual developmental disorder) or global developmental delay. From the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. (Copyright 2013). American Psychiatric Association, pp. 5051. until preschool or school age, when the social demands for peer inter action and group participation are higher. Social Communication and Social Interaction Individuals with ASD have difficulty understanding and engaging in social relationships. The problems are pervasive and affect three major areas: social emotional reciprocity, nonverbal communication, and understanding of social relationships. The presentation can vary with severity and developmental functioning. A diagnosis of ASD requires the presence of symptoms from all three categories (Table 58.3). Social Emotional Reciprocity Reduced social interactions in ASD may range from active avoidance or reduced social response to having an interest in, but lacking ability to initiate or sustain, an interaction with peers or adults. A young child with ASD may not respond when their name is called, may exhibit lim ited showing and sharing behaviors, and may prefer solitary play. In addition, the child may avoid attempts by others to play and may not participate in activities that require taking turns, such as peek a boo and ball play. An older child with ASD may have an interest in peers but may not know how to initiate or join in play. The child may have trouble understanding the rules of conversation and may either talk at length about an area of interest or abruptly exit the interaction. Younger children often have limited capacity for imaginative or pretend play. Older children may engage in play and conversation but lack flexibility and may be highly directive to peers. Some children with ASD interact well with adults but struggle to interact with same age peers. Nonverbal Communicative Behavior Difficulties with nonverbal communication may manifest as reduced or overly intense use of eye contact and gestures such as pointing. Children may also show reduced awareness or response to the eye gaze or pointing of others. They may use eye contact only when communicating a highly preferred request or may have difficulty coordinating the use of nonver bal with verbal communication. Children with ASD may have limited range of facial social communicative expression or expressed emotion. Developing, Maintaining, and Understanding Relationships Children with ASD have limited insight regarding social relationships. They may have difficulty understanding the difference between a true friend and a casual acquaintance, and even when the definitions are well understood, there may still be difficulty in developing and main taining more intimate relationships They have trouble picking up on the nuances of social interactions and understanding social expecta tions for polite behavior. They may have reduced understanding of per sonal boundaries and may stand too close to others. In addition, they can have trouble understanding and inferring others emotions and
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are less likely to share emotion or enjoyment with others. Adolescents and young adults have difficulty engaging in group interactions and navi gating romantic relationships. Restrictive and Repetitive Behavior A diagnosis of ASD requires the presence of two of the four symptoms of restrictive and repetitive patterns of behavior discussed next. Stereotyped Motor Movements or Speech Stereotyped (or stereotypic) movements and repetitive behaviors may include hand flapping, finger movements, body rocking and lunging, jumping, running and spinning, and repetitive speech such as echoing words immediately after they are said. Repetitive pat terns of play may be present, such as lining up objects, repetitively turning light switches on and off or opening and closing doors, spinning objects, or arranging toys in a specific manner. These repetitive patterns may not be seen in very young toddlers but may develop as they get older. Stereotyped movements can change over time and in older children are seen more often in individuals with lower cognitive functioning. Insistence on Sameness Children with ASD have difficulty tolerating transitions or change. They may insist on certain routines or schedules and can become very distressed with unexpected events or new situations. They may repeat scripts from shows or movies or watch the same portion of a video repeatedly. Intolerance for change can cause significant impairment and irritability and have an effect on child and family function. Restricted Interests This symptom may manifest as interests that seem of greater intensity when compared to same age peers. Younger children may play with a limited range of toys or may insist on retaining a small object in each hand. Older children may have a strong preference for a particular story or movie. The area of interest may be shared by peers (e.g., Dis ney movies, Legos, Thomas the Train) but unusual in its intensity. Other affected children may have interests that are both intense and Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 58 u Autism Spectrum Disorder 375 unusual, such as an interest in brands of vehicles, license plate num bers, or fans and heating systems. These interests interfere with social interactions; a child may only want to talk about their area of interest or may insist that peers act out a particular story in a rigid and inflex ible manner. Hyporeactivity or Hyperreactivity to Sensory Input Children with ASD may be overly sensitive to sensory input, such as noise, smells, or texture. Children may scream or react strongly when they hear a siren or vacuum and may gag and choke with cer tain foods or odors. They may refuse to wear certain clothing or may become very distressed with bathing or with cutting nails and hair. Conversely, some affected children seem to crave sensory input. They may engage in repetitive jumping or hugging and may smell or lick objects or people. Young children
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may inappropriately touch the face or hair of others. Diagnosing ASD with DSM 5 criteria can be challenging in very young children because of reduced expression of repetitive behaviors, particularly stereotyped behavior and intense interests. Studies moni toring development in high risk young children who have an older sibling with ASD indicate these additional symptoms may emerge over time. This creates a dilemma for specialty clinicians evaluating very young children for ASD, because they may not be able to endorse sufficient symptoms to make an early diagnosis and access specialized intervention services. Severity Levels Defined in DSM 5 Severity levels in ASD are based on the level of support the individual requires in each of the major domains impactedsocial communica tion and restricted interests and repetitive behavior. Levels range from needing support (level 1), to needing substantial support (level 2), to needing very substantial support (level 3) (Table 58.4). Specifiers Defined in DSM 5 A formal diagnosis of ASD also includes documenting associated conditions, including whether the individual has cognitive andor language impairment; any related medical, genetic, or environmen tal factors; and any other neurodevelopmental or behavioral health conditions, including catatonia (Table 58.5). This process helps to better characterize the presentation in an individual child and ensures that the diagnosis has been made by considering the symp toms in the context of the childs current cognitive and language abilities. EPIDEMIOLOGY The prevalence of ASD is estimated at 1 in 36 persons by the U.S. Centers for Disease Control and Prevention (CDC). This infor mation comes from prevalence data of 8 year olds derived from 11 sites participating in the Autism and Developmental Disabili ties Network (ADDM) and shows a greater than 300 increase in prevalence since systematic surveillance began in the year 2000. The increased prevalence relates, at least in part, to improved diag nosis and case finding, as well as inclusion of less severe presenta tions within the autism spectrum. There is a 4:1 male predominance, although new emerging information suggests that the prevalence in females may be higher than previously believed. Females with ASD often use camouflaging, which is intentionally or unconsciously hiding social communication difficulties by mimicking the facial expressions of others, having more effective compensatory behav iors, and displaying less clearly unusual preoccupying interests. All of these things, including clinician bias, may decrease girls with ASD being diagnosed. The prevalence is increased in siblings (up to 18 recurrence rate) and particularly in identical twins. There are no racial or ethnic differences in prevalence. Individuals from racial minorities and lower socioeconomic status are at risk for later Table 58.3 Signs and Symptoms of Possible Autism in Preschool Children (or Equivalent Mental Age) Spoken Language Language delay (in babbling or using words; e.g., using 10 words by age 2 yr). Regression in, or loss of, use of speech. Spoken language (if present) may include unusual features, such as vocalizations that are not speechlike; odd or flat intonation; frequent repetition of set words and phrases (echolalia); reference to self
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by name or you or she or he beyond age 3 yr. Reduced andor infrequent use of language for communication (e.g., use of single words, although able to speak in sentences). Responding to Others Absent or delayed response to name being called, despite normal hearing. Reduced or absent responsive social smiling. Reduced or absent responsiveness to other peoples facial expressions or feelings. Unusually negative response to the requests of others (demand avoidance behavior). Rejection of cuddles initiated by parent or caregiver, although the child may initiate cuddles. Interacting with Others Reduced or absent awareness of personal space, or unusually intolerant of people entering their personal space. Reduced or absent social interest in others, including children of own agemay reject others; if interested in others, child may approach others inappropriately, seeming to be aggressive or disruptive. Reduced or absent imitation of others actions. Reduced or absent initiation of social play with others; plays alone. Reduced or absent enjoyment of situations that most children like (e.g., birthday parties). Reduced or absent sharing of enjoyment. Eye Contact, Pointing, and Other Gestures Reduced or absent use of gestures and facial expressions to communicate (although may place an adults hand on objects). Reduced and poorly integrated gestures, facial expressions, body orientation, eye contact (looking at peoples eyes when speaking), and speech used in social communication. Reduced or absent social use of eye contact (assuming adequate vision). Reduced or absent joint attention (when one person alerts another to something by means of gazing, finger pointing, or other verbal or nonverbal indication for the purpose of sharing interest). This would be evident in the child from lack of: Gaze switching Following a point (looking where the other person points tomay look at hand) Using pointing at or showing objects to share interest Ideas and Imagination Reduced or absent imagination and variety of pretend play. Unusual or Restricted Interests andor Rigid and Repetitive Behaviors Repetitive stereotypic movements such as hand flapping, body rocking while standing, spinning, and finger flicking. Repetitive or stereotyped play (e.g., opening and closing doors). Overfocused or unusual interests. Excessive insistence on following own agenda. Extremes of emotional reactivity to change or new situations; insistence on things being the same. Overreaction or underreaction to sensory stimuli, such as textures, sounds, or smells. Excessive reaction to the taste, smell, texture, or appearance of food, or having extreme food fads. Adapted from Baird G, Douglas HR, Murphy MS. Recognizing and diagnosing autism in children and young people: Summary of NICE guidance. BMJ. 2011;343:d6360, Box 1, p. 901. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 376 Part IV u Learning and Developmental Disorders diagnosis, although the most recent prevalence data suggest that this gap is closing. ETIOLOGY The etiology of ASD is thought to result from disrupted neural con nectivity and is primarily impacted by genetic variations affecting early brain development.
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Animal models and studies of individuals with ASD indicate changes in brain volume and neural cell density in the limbic system, cerebellum, and frontotemporal regions. One study documented changes in early brain development, character ized as hyperexpansion of cortical surface area, at age 6 12 months on brain MRI, which correlated with later development of impaired social skills. Functional studies show abnormalities of processing information, particularly related to foundational social skills such as facial recognition. The disruptions in early brain development likely are responsive to treatment. Early developmental therapies in young children with ASD have demonstrated the capacity for nor malization of electrophysiologic response to visual stimuli, includ ing faces. Numerous genes involved in brain development and synaptic func tion have been associated with ASD. Pathogenic variants that include large genetic deletions or duplications and small sequencing changes have been implicated; these can be inherited or occur de novo. Hetero zygous mutations in genes, such as present in deletion or duplication of 15q11.2 or 16p11.2, may have variable expression within a family. Rare recessive mutations have been implicated in some populations with high levels of consanguinity. Patients with a number of genetic syndromes (e.g., fragile X, Down, Smith Lemli Opitz, Rett, Angelman, Timothy, Joubert), as well as disorders of metabolism and mitochon drial function have higher rates of ASD than the general population (Tables 58.5, 58.6, and 58.7). There is also possible evidence for environmental contributions to ASD. Older maternal or paternal age may increase the risk of ASD. In addition, factors influencing the intrauterine environment, such as maternal obesity or overweight, short interval from prior pregnancy, premature birth, and certain prenatal infections (e.g., rubella, cyto megalovirus), are associated with ASD. Population level associations have been investigated for environmental toxins such as organophos phates, pesticides, air pollution, and volatile organic compounds. An epigenetic model is considered one explanation for the etiology; indi viduals with genetic vulnerability may be more sensitive to environ mental factors influencing early brain development. Despite frequent concerns from families that vaccines or the pre servatives in vaccines lead to ASD, there is no evidence to support this claim. Multiple research studies and meta analyses have failed to show an association of vaccines with ASD. No biomarkers are available yet, but there is emerging evidence from neuroimaging findings, electrophysiologic testing, and eye tracking that hold the promise for presymptomatic detection along with accu rate clinical diagnosis and prognostic assessment. DIFFERENTIAL DIAGNOSIS The differential diagnosis of ASD is complex because many conditions in the differential can also occur with ASD. The most important condi tions to consider in young children are language disorder (see Chapter 53), ID or GDD (Chapter 56), and hearing loss (Chapter 55). Children with language disorder may have impairments in social commu nication and play; their social and play skills, however, are typically on par with their language level. In addition, they do not have asso ciated restricted and repetitive behavior or atypical use of language, such as scripting. The diagnosis of social communication
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disorder is also distinguished from ASD by the lack of restrictive and repeti tive behaviors. Children with ID or GDD may have delays in social and communication skills as well as stereotyped behavior. However, social and communication skills are typically commensurate with their cognitive and adaptive functioning. Children with hearing loss may present with some red flags for ASD, such as poor response to name. However, they typically develop nonverbal communication and play skills as expected and do not have stereotyped or restricted behavior patterns. In older children, disorders of attention, learning, and mood regula tion must be considered in the differential diagnosis of ASD. Children with attention deficithyperactivity disorder (ADHD) may pres ent with reduced eye contact and response to name caused by poor attention rather than lack of social awareness. Children with ADHD, however, do not have associated impairments in shared enjoyment and social reciprocity or repetitive behaviors. Children with social anxiety or other anxiety disorders may present with some symptoms suggestive of ASD. Shy children may have reduced eye contact and social initia tion. Anxious children can be resistant to change and prefer familiar routines. Children with anxiety, however, typically will have preserved social interest and insight and will not exhibit high levels of stereotyped behaviors. Reactive attachment disorder can be difficult to distinguish from ASD, particularly in younger children with a history of prolonged Table 58.4 DSM 5 Severity Levels for Autism Spectrum Disorder SEVERITY LEVEL SOCIAL COMMUNICATION RESTRICTED, REPETITIVE BEHAVIORS Level 3 Requiring very substantial support Severe deficits in verbal and nonverbal social communication skills cause severe impairments in functioning, very limited initiation of social interactions, and minimal response to social overtures from others. For example, a person with few words of intelligible speech who rarely initiates interaction and, when he or she does, makes unusual approaches to meet needs only and responds to only very direct social approaches. Inflexibility of behavior, extreme difficulty coping with change, or other restricted repetitive behaviors markedly interfere with functioning in all spheres. Great distress difficulty changing focus or action. Level 2 Requiring substantial support Marked deficits in verbal and nonverbal social communication skills; social impairments apparent even with supports in place; limited initiation of social interactions; and reduced or abnormal responses to social overtures from others. For example, a person who speaks simple sentences, whose interaction is limited to narrow special interests, and who has markedly odd nonverbal communication. Inflexibility of behavior, difficulty coping with change, or other restrictedrepetitive behaviors appear frequently enough to be obvious to the casual observer and interfere with functioning in a variety of contexts. Distress andor difficulty changing focus or action. Level 1 Requiring support Without supports in place, deficits in social communication cause noticeable impairments. Difficulty initiating social interactions, and clear examples of atypical or unsuccessful responses to social overtures of others. May appear to have decreased interest in social interactions. For example, a person who is able to speak in full sentences and engages in communication but whose to and fro
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conversation with others fails and whose attempts to make friends are odd and typically unsuccessful. Inflexibility of behavior causes significant interference with functioning in one or more contexts. Difficulty switching between activities. Problems of organization and planning hamper independence. From the Diagnostic and Statistical Manual of Mental Disorders, 5th ed (Copyright 2013). American Psychiatric Association, p. 52. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 58 u Autism Spectrum Disorder 377 Table 58.5 Common Co occurring Conditions in Autism Spectrum Disorder (ASD) COMORBIDITY INDIVIDUALS WITH AUTISM AFFECTED COMMENTS DEVELOPMENTAL DISORDERS Intellectual disability 45 Prevalence estimate is affected by the diagnostic boundary and definition of intelligence (e.g., whether verbal ability is used as a criterion). In individuals, discrepant performance between subtests is common. Language disorders Variable An autism specific language profile (separate from language disorders) exists, but with substantial interindividual variability. Tic disorders 1438 6.5 have Tourette syndrome. Motor abnormality 79 See Table 58.2. GENERAL MEDICAL DISORDERS Epilepsy 3546 Increased frequency in individuals with intellectual disability or genetic syndromes. Two peaks of onset: early childhood and adolescence. Increases risk of poor outcome. Gastrointestinal problems 970 Common symptoms include chronic constipation, abdominal pain, chronic diarrhea, cyclic vomiting, and gastroesophageal reflux. Associated disorders include gastritis, esophagitis, gastroesophageal reflux disease, inflammatory bowel disease, celiac disease, Crohn disease, and colitis. Immune dysregulation 38 Associated with allergic and autoimmune disorders. Genetic disorders 1020 Collectively called syndromic autism. Examples include fragile X syndrome (2150 of individuals affected have autism), Rett syndrome (most have autistic features but with profiles different from idiopathic autism), tuberous sclerosis complex (2460), Down syndrome (539), phenylketonuria (520), CHARGE syndrome (1550), Angelman syndrome (5081), Timothy syndrome (6070), and Joubert syndrome (40). Sleep disorders 5080 Insomnia is the most common. BEHAVIORAL HEALTH DISORDERS Any behavioral health disorder 7090 ADHD 4070 Anxiety 40 Common across all age groups. Most common are social anxiety disorder (1329 of individuals with autism) and generalized anxiety disorder (1322). High functioning individuals are more susceptible (or symptoms are more detectable). Catatonia Unknown Autism shutdown disorder similar to Down syndrome disintegrative disorder (see Chapters 47.3 and 57). Depression 1270 Common in adults, less common in children. High functioning adults who are less socially impaired are more susceptible (or symptoms are more detectable). Obsessive compulsive disorder (OCD) 724 Shares the repetitive behavior domain with autism that could cut across nosologic categories. Important to distinguish between repetitive behaviors that do not involve intrusive, anxiety causing thoughts or obsessions (part of autism) and those that do (and are part of OCD). Psychotic disorders 1217 Mainly in adults. Most commonly recurrent hallucinosis. High frequency of autism like features (even a diagnosis of ASD) preceding adult onset (52) and childhood onset schizophrenia (3050). Substance use disorders 16 Potentially because individual is using substances as self medication to relieve anxiety. Oppositional defiant disorder 1628 Oppositional behaviors could be a manifestation of
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anxiety, resistance to change, stubborn belief in the correctness of own point of view, difficulty seeing anothers point of view, poor awareness of the effect of own behavior on others, or no interest in social compliance. Eating disorders 1021 Avoidantrestrictive food intake may lead to nutrient deficiencies and poor growth. PERSONALITY DISORDERS Paranoid personality disorder 019 Could be secondary to difficulty understanding others intentions and negative interpersonal experiences. Schizoid personality disorder 2126 Partly overlapping diagnostic criteria. Schizotypal personality disorder 213 Some overlapping criteria, especially those shared with schizoid personality disorder. Borderline personality disorder 09 Could have similarity in behaviors (e.g., difficulties in interpersonal relationships, misattributing hostile intentions, problems with affect regulation), which requires careful differential diagnosis. Could be a misdiagnosis of autism, particularly in females. Obsessive compulsive personality disorder 1932 Partly overlapping diagnostic criteria. Avoidant personality disorder 1325 Could be secondary to repeated failure in social experiences. Continued Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 378 Part IV u Learning and Developmental Disorders neglect or trauma. However, social behaviors in these children gener ally improve with positive caretaking. The differentiation of ASD from obsessive compulsive disorder (OCD), tics, and stereotyped behaviors can sometimes be challenging. In general, stereotyped behaviors may be calming or preferred, whereas tics and compulsive routines generally are distressing to the individual. Children with OCD have intense interests, as well as repetitive behav iors and rituals, but do not have impairment in social communication or interaction. Children with stereotypic movement disorder will not have impaired social skills or other types of restricted and repetitive behaviors. Children with Landau Kleffner syndrome (LKS) present with a loss of skills in language comprehension (auditory verbal agno sia) and verbal expression (aphasia) associated with onset of epileptic seizures during sleep (see Chapter 53). In contrast to ASD, children with LKS usually present with typical early development followed by loss of language function at age 3 6 years. CO OCCURRING CONDITIONS Between 35 and 50 of individuals with ASD have ID, ranging in severity from mild to severe (see Table 58.5). An additional 23 of children have intellectual functioning in the borderline range (IQ 71 85), and approximately 40 of individuals with ASD are non verbal. ID is associated with higher rates of both identified genetic conditions and epilepsy. Children with ASD often have associated language impairments, including delays in expressive, receptive, and pragmatic (social) language skills. Language function can range Table 58.5 Common Co occurring Conditions in Autism Spectrum Disorder (ASD)contd COMORBIDITY INDIVIDUALS WITH AUTISM AFFECTED COMMENTS BEHAVIORAL DISORDERS Aggressive behaviors 68 Often directed toward caregivers rather than noncaregivers. Could be a result of empathy difficulties, anxiety, sensory overload, disruption of routines, and difficulties with communication. Self injurious behaviors 50 Associated with impulsivity and hyperactivity, negative affect, and lower levels of ability and speech. Could signal frustration in individuals with reduced communication, as well
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as anxiety, sensory overload, or disruption of routines. Could also become a repetitive habit. Could cause tissue damage and need for restraint. Pica 36 More likely in individuals with intellectual disability. Could be a result of a lack of social conformity to cultural categories of what is deemed edible, or sensory exploration, or both. Suicidal ideation or attempt 1114 Risks increase with concurrent depression and behavioral problems and after being teased or bullied. Coloboma of the eye; heart defects; atresia of the choanae; retardation of growth and development, or both; genital and urinary abnormalities, or both; and ear abnormalities and deafness. Particularly in high functioning adults. DSM IV, Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition; DSM 5, Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Adapted from Lai MC, Lombardo MV, Baron Cohen S. Autism. Lancet. 2014;383:896910. Table 58.6 Syndromes with Autistic Like Behaviors CHROMOSOME DELETIONS 1q21 7q11.28 16p11.2 17q12 2q23.1 (MBD5) 12q24.3 Cri du chat (5p15.2 p15.33) 22q deletion syndrome Jacobsen (11q23.2) Phelan McDermid (SHANK3; 22q13) PittHopkins (18q21.2) CHROMOSOME DUPLICATIONS 15q11.1 q13.3 7q11.23 18q12.2 16p11.2 1q21.1 22q11.2 PotockiLupski (17p11.2) EPILEPSY ENCEPHALOPATHIES, EPILEPSY Cortical dysplasia focal epilepsy SCN1A related syndromes (Dravet, Lennox Gastaut, others) Early myoclonic encephalopathies (Ohtahara: STXBP1, ARX, SIK1) SCN2A related syndromes (West, others) SLC6A1 myotonic atonic epilepsy HCN1 related epilepsies CDKL5 SCN8A PCDH19 SCL35A2 related disorders Epilepsy aphasia spectrum (Landau Kleffner; GRIN2A; continuous spike wave during low wave sleep) Juvenile myoclonic epilepsy (RING2) OTHER SYNDROMES 2q37 monosomy Angelman Bardet Biedl Cardiofaciocutaneous CHARGE association Cohen Congenital rubella Cornelia de Lange Costello FOXG1 variants Fragile X Hypomelanosis of Ito Joubert Kleefstra (EHMT1) Lujan Fryns Moebius sequence Muscle eye brain disease Myotonic dystrophy Neurofibromatosis Nonsyndromic intellectual disability due to SYNGAP1 variants Noonan Oculoauriculovertebral spectrum (including Goldenhar) Partial monosomy 1p36 Partial tetrasomy 15 Prader Willi PTEN variants Rett complex (female male) Ring chromosome 14 SETD1B variants Sex chromosome aneuploidies Sashi Pena (ASXL2) Smith Lemli Opitz Smith Magenis Sotos Timothy Tolchin Le Caignec (TOLCAS) Trisomy 21 Tuberous sclerosis WAGR Wiedemann Steiner (KMT2A) Williams Italics denoted affected gene Modified from Kliegman RM, Toth H, Bordini BJ, Basel D, eds. Nelson Pediatric Symptom Based Diagnosis, 2nd ed. Philadelphia: Elsevier; 2023: Table 32.6, p. 537. Table 58.7 Inborn Errors of Metabolism with Autistic Like Behavior Adenylosuccinate lyase deficiency Biotinidase deficiency Cerebral creatinine deficiency Cerebral folate deficiency Ceroid lipofuscinosis (infantile) Cystathionine synthase deficiency Dihydropyrimidinase deficiency Disorders of creatine transport or metabolism Homocystinuria Lesch Nyhan syndrome Methylenetetrahydrofolate reductase deficiency Mitochondrial disorders Mucopolysaccharidosis Phenylketonuria (untreated) Modified from Kliegman RM, Toth H, Bordini BJ, Basel D, eds. Nelson Pediatric Symptom Based Diagnosis, 2nd ed. Philadelphia: Elsevier; 2023: Table 32.8, p. 539. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 58 u Autism Spectrum Disorder 379 widely from nonverbal status to age appropriate. Gastrointestinal (GI) problems such as cyclic vomiting, constipation, esophagitis, and gastroesophageal reflux disease (GERD) are reported in
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up to 70 of children with ASD. Epilepsy occurs in up to 3546 of chil dren with ASD and presents in two peaks: in early childhood and in adolescence. Children with ID, female gender, and lower gestational age are at higher risk for having seizures. Overall, between 70 and 90 of children with ASD are identified as having a co occurring behavioral health condition, with ADHD being the most common, occurring in between 40 and 70 of chil dren with ASD. There are higher rates of anxiety (40) and mood disorders in ASD, particularly during adolescence. Children with ASD are also at increased risk for being bullied and may present with sec ondary irritability, anxiety, or depression. Adolescents may develop gender nonconforming roles, gender variance, and transgender identi ties; this may also lead to being bullied. Children with ASD are at high risk for suicidal ideation and attempts. Catatonia can also occur, most commonly developing during the teenage years, and may present with changes in activity level, unusual movements, and behavioral regres sion or loss of skills (Chapter 47.3). Sleep problems, including delayed sleep onset, frequent night wak ing, and abnormal sleep architecture, are reported in 5080 of chil dren with ASD. There is some evidence for baseline abnormalities in melatonin secretion. The use of screen based activities such as tele vision, computers, or tablets before bedtime can inhibit melatonin secretion. Children with ASD commonly have high rates of feeding and toileting problems resulting from resistance to change, sensory sensitivity, and repetitive behavior patterns. Many children with ASD have restrictive feeding patterns and food selectivity. DSM 5 introduced the diagnosis of avoidant and restrictive food intake disorder (ARFID) that, although not specific to children with ASD, describes a pattern of a severely disturbed eating experience resulting in nutritional deficiency or inadequate weight gain and may affect as many as 21 of children with ASD. Restrictive eating patterns may lead to nutritional deficiencies, such as scurvy, rick ets, anemia, or protein malnutrition. Children with ASD also have higher rates of overweight, possibly because of diets higher in car bohydrates, reduced physical activity, use of food rewards to regu late behavior, and side effects from medications used for managing mood and behavior. As many as 25 of preschool age children with ASD have pica (eating of nonfood items), and this tends to persist in children with co occurring ID. Self injury and aggression are common in ASD patients, but most common in individuals with lower cognitive function and limited lan guage. Sleep deprivation, nutritional deficits, pain, epilepsy, and medi cation side effects may contribute to these behaviors. Wandering frequently co occurs with ASD, with nearly 50 of chil dren between 4 and 10 years of age reported as trying to elope. In chil dren who were missing long enough to call the police, approximately 66 were at risk for traffic related injury and nearly 30 had near drowning events, which is the leading cause of death in children who wander. SCREENING The
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American Academy of Pediatrics recommends screening for ASD for all children at age 18 months and 24 months (see Chapter 28). Screening should also occur when there is increased risk for ASD, such as a child with an older sibling who has ASD, or whenever there is concern for possible ASD. Screening can be done by a parent checklist or direct assessment. The most frequently used screening tool is the Modified Checklist for Autism, RevisedFollow Up Interview (MCHAT RFU), a 20 item parent report measure, with additional standardized parent interview completed for intermediate scores. The MCHAT R FU can be used from age 16 30 months. Children who score 8 or between 3 and 7 after the parent interview are at high risk for a diag nosis of ASD or some developmental delay. The Parents Observation of Social Interaction (POSI) is another commonly used autism specific screener. It includes seven items. ASSESSMENT Diagnostic assessment optimally should include medical evaluation and assessment of the childs cognitive, language, and adaptive func tion. Developmental behavioral pediatricians, neurodevelopmental disability specialists, neurologists, psychiatrists, and psychologists are qualified to make a formal diagnosis of ASD. Other specialists, includ ing speech language pathologists and occupational therapists, should also be included depending on the childs age and the presenting concerns. Assessment of ASD includes direct observation of the child to evaluate social communicative skills and behavior. Informal obser vation can be supplemented with structured diagnostic tools such as the Autism Diagnostic Observation Schedule, Second Edition (ADOS 2) or the Toddler module (ADOS T). These structured play based assessments provide social prompts and opportunities to evaluate the frequency and quality of a childs social responsiveness to, initiation, and maintenance of social interactions, the capacity for joint atten tion and shared enjoyment; the childs behavioral flexibility; and the presence of repetitive patterns of behavior and preoccupying inter ests. These measures also provide some understanding of a childs insight about social relationships and emotional awareness. The ADOS 2 and ADOS T are not required for accurate diagnosis and do not stand alone, but rather can be used to augment a careful history and observation. The Childhood Autism Rating Scale, Second Edition (CARS 2) is a 15 item direct clinical observation instrument that can assist clinicians in the diagnosis of ASD. The Autism Diagnostic Interview Revised (ADI R) is a lengthy clinical interview tool that is used primarily in research settings because it takes several hours to administer. Other tools include standardized rating scales, such as the Social Responsiveness Scale or the Social Communication Ques tionnaire, that parents and teachers can complete to report on the childs social skills and behaviors. There is an emergence of the use of telehealth to assess children with ASD, and preliminary studies have suggested that 80 of children could be determined to have or not have ASD with reasonable certainty. Medical evaluation should include a thorough history and detailed physical examination of the child, including direct behavioral observa tions of communication and play. In addition, the
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examination should include measurement of head circumference, careful evaluation for dysmorphic features, and screening for tuberous sclerosis with Wood lamp exam. Children with ASD should have genetic testing, an audiol ogy examination to rule out hearing loss, and in children with pica, a lead test (Table 58.8). There are currently several specialty specific clinical guidelines for genetic evaluation of children diagnosed with ASD. Genetic testing is shown to impact clinical decision making, but no studies have evalu ated the impact of genetic testing on the outcome for the child. The American College of Medical Genetics recommends a tiered approach to genetic testing. Initial Etiologic Assessment All children with ASD should have a chromosomal microarray (CMA). CMA will be positive in 1015 of individuals with ASD. The rate is increased to almost 30 in individuals who have complex presentations, such as associated microcephaly, dysmorphic features, congenital anomalies, or seizures. CMA technology will identify copy number variants but not DNA sequencing errors, balanced transloca tions, or abnormalities in trinucleotide repeat length. Fragile X DNA testing is recommended for all males with ASD. Fragile X testing should also be considered in females with physical features suggestive of frag ile X syndrome or with a family history of fragile X, X linked pattern of ID, tremorataxia, or premature ovarian failure (see Chapter 59). Second Tier Etiologic Assessment Females with ASD should have testing for pathologic variants in the MeCP2 gene. Males who have hypotonia, drooling, and frequent respi ratory infections should have MeCP2 deletionduplication testing. All individuals with ASD and a head circumference greater than 2.5 Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 380 Part IV u Learning and Developmental Disorders standard deviations (SD) above the mean should have testing for patho logic variants in the PTEN gene because there is a risk for hamartoma tumor disorders (Cowden, Proteus like, Bannayan Riley Ruvakaba syndromes) in these individuals. Cytogenetic testing (karyotype) has a lower yield than CMA. Karyotype is recommended if microarray is not available and in children with suspected balanced translocation, such as history of multiple prior miscarriages. Further medical diagnostic testing is indicated by the childs history and presentation. Brain imaging (MRI) is indicated in cases of micro cephaly, significant developmental regression, seizures, or focal findings on neurologic examination. Because of the high rate (up to 25) of mac rocephaly in ASD, imaging is not indicated for macrocephaly alone. MRI is not recommended for minor language regression (loss of a few words) during the second year of life that is often described in toddlers with ASD. Children with concern for seizures, spells, or developmental regres sion should have an electroencephalogram (EEG). Metabolic screening is indicated for children with signs of a metabolic or mitochondrial disor der, such as developmental regression, weakness, fatigue, lethargy, cyclic vomiting, or seizures (see Table 58.7 and Chapters 56 and 104). Next
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Generation Sequencing Whole exome sequencing (WES) can identify single nucleotide vari ants, including pathogenic loss of function mutations and missense mutations; studies have identified a molecular diagnosis in nearly 30 of individuals tested because of the presence of a neurodevelopmental disorder. If the initial genetic testing is negative, clinicians should con sider ordering this test in conjunction with genetic counseling to aid in understanding results. TREATMENT AND MANAGEMENT Approaches to Intervention The primary treatment for ASD is done outside the medical setting and includes developmental and educational programming (Fig. 58.1). Numerous resources have been developed that can help families in the complex process of treatment planning (Table 58.9). Intensive behav ioral therapies have the strongest evidence to date. Earlier age at ini tiation of treatment and higher intensity of treatment are associated with better outcomes, although recent studies comparing two different treatments at different levels of intensity (15 vs 25 hrwk) did not show significant differences between groups in any of the outcomes assessed. Programming must be individualized, and no approach is successful for all children. In addition, research treatments are often conducted with a high level of intensity and fidelity that is difficult to scale up or reproduce in community settings. Higher cognitive, play, and joint attention skills and lower symptom severity at baseline are predictors for better outcomes in core symptoms, intellectual function, and lan guage function. There are many evidence based approaches to treating children with ASD, with three main approaches identified. The intervention with the strongest evidence base is applied behavioral analysis (ABA), which is based on the principles of direct incremental teaching of skills within a traditional behavioral framework using reinforcement of desired behavior, careful data collection, and analysis and adjustment of the treatment program based on review of data. The second is develop mental relationship based intervention (DRBI), which includes parent mediated interventions that focus on building warm, mean ingful interaction to improve communication, learning, and problem solving. The best known approach in this category is Floortime. The third approach is the naturalistic developmental behavioral inter vention, which builds upon ABA to incorporate more choices for chil dren and is implemented in natural situations. Comprehensive models integrating behavioral and developmental approaches that build on key foundational skills, such as joint attention, shared enjoyment, and reciprocal communication, show strong evidence of efficacy for young children, particularly toddlers, with ASD. Examples include the Early Start Denver Model (ESDM), Joint Attention Symbolic Play Engagement and Regulation (JASPER), and Social CommunicationEmotional Regu lationTransactional Support (SCERTS). Educational approaches such as the Treatment and Education of Autistic and Communication Handicapped Children (TEACCH) incor porate structured teaching, visual supports, and adjustment of the environment to the individual needs of students with ASD, such as dif ficulty with communication, understanding time, and need for routine. These approaches have demonstrated efficacy for improved cognitive and adaptive skills. For older children with more severe symptoms, approaches that use behavioral principles in addition to adjusting the environment may be most effective. Speech and language therapy
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can help build vocabulary, comprehen sion, and pragmatic skills. Children with ASD benefit from visual supports for comprehension, understanding expectations, and communicating their needs. Augmentative communication approaches using photographs or picture icons can improve comprehension and ability to communicate (see Chapter 54). There are a range of options with varying levels of complex ity, flexibility, and technology. Using augmentative communication does not inhibit acquisition of verbal language. On the contrary, supporting a childs language development with augmentative supports can facilitate the development of spoken language, even in older children. Additional strategies to build social skills are used for school age children and adolescents and may be administered in the school or community setting by a variety of specialists, including speech therapists, psychologists, and counselors. Social skills programs that include training peer mentors have higher rates of efficacy. Table 58.8 Medical and Genetic Evaluation of Children with Autism Spectrum Disorder PHYSICAL EXAMINATION Dysmorphic physical features Muscle tone and reflexes Head circumference Wood lamp examination for tuberous sclerosis DIAGNOSTIC TESTING Chromosomal microarray (CMA) in all individuals Fragile X DNA test in males Audiology and vision evaluation Lead test in children with pica ADDITIONAL TARGETED GENETIC TESTING Fragile X DNA test in females with symptoms suggestive of fragile X, family history of X linked intellectual disability, tremor, ataxia, or premature ovarian failure MeCP2 sequencing in females PTEN testing if head circumference 2.5 standard deviations (SD) above the mean MeCP2 deletionduplication testing in males with significant developmental regression, drooling, respiratory infections, and hypotonia Karyotype if unable to obtain CMA or if balanced translocation suspected ADDITIONAL TARGETED DIAGNOSTIC TESTING Electroencephalogram (EEG) in children with seizures, staring spells, or developmental regression Brain MRI in children with dysmorphology, microcephaly, focal neurologic findings, seizures, severe hypotonia, or developmental regression Metabolic testing in children with developmental regression, hypotonia, seizures, food intolerance, cyclic vomiting, lethargy, hearing loss, ataxia, or course facial features Exome or genome sequencing if atypical features are present (behavioral or dysmorphic) (see Table 56.1) Data from Schaefer GB, Mendelsohn NJ. Clinical genetics evaluation in identifying the etiology of autism spectrum disorders: 2013 guideline revisions. Genet Med. 2013;15(5):399407 and Lord C, Charman T, Havdahl A, et al. The Lancet Commission on the future of care and clinical research in autism. Lancet. 2022;399:271326. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 58 u Autism Spectrum Disorder 381 Occupational and physical therapy may be indicated for individu als with motor delay and difficulty acquiring adaptive skills such as dressing and toileting. For some high school students with ASD, training in life skills and vocational skills is critical for maximizing independence in adulthood. Training may focus on basic self care (e.g., dressing, hygiene), functional academics (e.g., money management, banking skills), learning to fill out a job application, and understanding how to behave with strangers and in work settings. Social skills and job coaching may
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be needed even for adolescents with strong cognitive and academic function, because they may struggle with social per ception and may be vulnerable to exploitation by others. There continue to be disparities in regard to accessing care, with racially and ethnically minoritized groups and children from low income families showing less access to acute care and specialized, com munity and educational services, when compared with higher income and White families. Co occurring Conditions Additional medical or behavioral health treatment is often required for the management of co occurring conditions in ASD. Seizures occur in up to 35 of children with ASD and should be man aged with appropriate antiepileptic therapy (see Chapter 633). GI problems (e.g., cyclic vomiting, constipation, esophagitis, GERD) may present with nonspecific irritability, sleep disturbance, self injury, aggression, and signs of pain or discomfort, such as crying, and can be managed with the same approaches used in typically Family Community (preschool childcare) School or community School or community Community Child Child Adolescent Adult Family Family Family Preschool age (before the age of 6 years) School age (between the ages of 6 and 11 years) Adolescence (between the ages of 12 and 17 years) Adults (18 years and older) Family Family psychoeducation Family coaching around core features Parentmediated treatments (eg, JASPER, Early Social Interaction, and PACT) Behavior management (as advocates) Child Specific shortterm therapies (eg, JASPER) General approaches (eg, PRT, Project ImPACT, and DTT) Comprehensive curricula (eg, ESDM and Lovaas approach Specific disciplines (eg, occupational therapy and speech) Community Support in childcare and preschool (no evidence) ESDM classrooms TEACCH classrooms LEAP classrooms Family Behavior management (RUBI) Child General approaches (eg, PRT and DTT) Academic skills Social skills (eg, PEERS) Specific disciplines (eg, psychopharmacology) CBT (eg, Coping Cat and Facing your Fears) Community School inclusion Classes Special education Sports and community programs Family As supports in group Behavior management Adolescents CBT (eg, Coping Cat and BIACA) Social skills (eg, PEERS) Psychopharmacology Academic skills Community School inclusion Classes Special education Sports and community Family As advocates Adults CBT Social skills (eg, PEERS) Psychopharmacology Preemployment Community Support in education Support in employment Support in housing Sports and activities Project ImPACT job training Project SEARCH Fig. 58.1 Sources of support and locations of treatment. The size of each ellipse represents the extent of care or intervention received. BIACA, Behavioral Interventions for Anxiety in Children with Autism; CBT, cognitive behavioral therapy; DTT, discrete trial training; ESDM, Early Start Denver Model; ImPACT, Improving Parents as Communication Teachers; JASPER, Joint Attention, Symbolic Play, Engagement, and Regulation approach; LEAP, Learning Experiences and Alternative Program for Preschoolers and their Parents; PACT, Preschool Autism Communication Trial; PEERS, Program for the Education and Enrichment of Relational Skills; PRT, Pivotal Response Treatment; RUBI, Research Units in Behavioral Intervention; TEACCH, Treatment and Education of Autistic and Related Communication Handicapped Children program. (From Lord C, Charman T, Havdahl A, et al. The Lancet Commission on the future of care and clinical research in autism. Lancet. 2022;399:271326, Fig. 6, p. 287.) Table 58.9
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Autism Resources for Families Autism Speaks First 100 Days kit https:www.autismspeaks.orgfamily servicestool kits100 day kit Autism Speaks Toolkitsdental, transition, guardianship https:www.autismspeaks.orgfamily servicestool kits AACAP Autism Spectrum Disorder Parents Medication Guide https:www.aacap.orgAppThemesAACAPDocsresource centersautismAutismSpectrumDisorderParentsMedicat ionGuide.pdf Sexuality information for individuals with developmental disability http:vkc.mc.vanderbilt.eduhealthybodies Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 382 Part IV u Learning and Developmental Disorders developing children. Children with pica should have lead and iron levels monitored. Management of co occurring attention and mood disorders is similar to that for typically developing children. Strategies to increase structure and organization in the environment and use of visual supports (e.g., schedules) can improve attention and reduce anxiety. Some children with ASD benefit from modified cognitive behavioral therapy to address anxiety and OCD. (see Chapter 31). Strategies to promote sleep hygiene and use of behavioral approaches, such as structured bedtime routines, can address delayed sleep onset. Other medical problems, such as epilepsy or GERD, can also contribute to poor sleep and should be treated directly. In cases refractory to behavioral approaches, medications may be used. Structured behavioral approaches for delayed toilet training in concert with treatment to prevent constipation are often needed for children with ASD. For children with highly restrictive diets, nutrition counseling and behaviorally based feeding therapy may be needed to address poor caloric intake or lack of nutritional qual ity. Because of limited diets, children with ASD may be at risk for low levels of calcium, vitamins C and D, and iron. Children who are overweight may still have poor nutrition as a result of restrictive diets. Irritability is a nonspecific symptom and can be a reflection of pain, anxiety, distress, or lack of sleep. Children with ASD are prone to irri tability because of their difficulty tolerating change and their limited communication skills. Management of irritability includes evaluating carefully for medical problems that may be causing pain and for any factors in the childs home or school environment that may be caus ing distress. Possible causes of distress range from common experi ences such as changes in the routine to undisclosed abuse or bullying. Treatment should be targeted first at any underlying cause. Medica tions are often used to treat irritability in ASD, but should only be used after appropriate behavioral and communication supports have been implemented. Pharmacology There are currently no medications that treat the core symptoms of ASD. Medications can be used to target specific co occurring condi tions or symptoms (Table 58.10; see also Table 58.5). Families should be cautioned, however, that the effect size may be lower and the rate of medication side effects higher in children with ASD. Preliminary data suggested that intranasal therapy with neuropep tide oxytocin may improve social functioning in children with ASD, particularly those with low pretreatment oxytocin levels, but a recent randomized trial did not demonstrate any effect of oxytocin on
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social or cognitive functioning. There is evidence to support the use of stimulant medications, atomoxetine, and agonists for ADHD in ASD. Selective serotonin reuptake inhibitors (SSRIs) can be used for anxiety and OCD and in adolescents may also be useful for depression. Benzodiazepines may be useful for situational anxiety, for example, triggered by dental and medical procedures or air travel. Medications used to treat ADHD and anxiety may result in activation or irritability in ASD and require care ful monitoring. Melatonin can be used to improve sleep onset but will not address night waking. Clonidine or trazodone may be used for sleep onset and maintenance. No medications are specifically labeled for treatment of insomnia in ASD. The adrenergic agonists may be helpful in children who pres ent with significant behavioral dysregulation. There are two atypical antipsychotic medications that have U.S. Food and Drug Admin istration (FDA) recommendation for irritability and aggression in children with ASD. Both risperidone and aripiprazole have several studies documenting efficacy for reducing irritability, aggression, and self injury. Secondary improvements in attention and repeti tive behavior were also noted. Side effects include weight gain and metabolic syndrome, as well as tardive dyskinesia and extrapyra midal movements. Careful laboratory monitoring is recommended. Mood stabilizing antiepileptic medications have also been used to treat irritability. Table 58.10 Common Pharmacologic Treatments in Autism Spectrum Disorder (ASD) TARGET SYMPTOM MEDICATION CLASS EFFECTS SIDE EFFECTS MONITORING Hyperactivity andor Inattention Stimulants Decreased hyperactivity, impulsivity, improved attention Activation, irritability, emotional lability, lethargysocial withdrawal, stomach ache, reduced appetite, insomnia, increased stereotypy Height, weight, BP, HR 2 Agonists Decreased hyperactivity, impulsivity, improved attention Drowsiness, irritability, enuresis, decreased appetite, dry mouth, hypotension Height, weight, BP, HR Selective norepinephrine reuptake inhibitor Decreased hyperactivity, impulsivity, improved attention Irritability, decreased appetite, fatigue, stomach ache, nausea, vomiting, racing heart rate Height, weight, BP, HR Anxiety Selective serotonin reuptake inhibitors Decreased anxiety Activation, hyperactivity, inattention, sedation, change in appetite, insomnia, stomachache, diarrhea Citalopram: prolonged QTc interval Weight, BP, HR Irritability Atypical antipsychotics (risperidone, aripiprazole) Decreased irritability, aggression, self injurious behavior, repetitive behavior, hyperactivity Somnolence, weight gain, extrapyramidal movements, drooling, tremor, dizziness, vomiting, gynecomastia Weight, BP, HR Monitor CBC, cholesterol, ALT, AST, prolactin, glucose or hemoglobin A1c Insomnia Melatonin Shortened sleep onset Nightmares, enuresis Specific medication names are provided in parentheses when there is a Food and Drug Administration (FDA)approved indication for the use of the medication to treat the symptom in children with ASD. Further information about these medications is available in Chapter 33. BP, Blood pressure; HR, heart rate; CBC, complete blood count; ALT, alanine transaminase; AST, aspartate transaminase. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 59 u Fragile X Syndromes 383 Complementary and Alternative Medicine Families of children with ASD often use complementary and alter native medicine (CAM) approaches. These treatments can include supplements, dietary changes, and body or physical treatments. There is
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limited evidence to inform families, who often learn about these treatments from friends and family members, alternative medicine providers, or the internet. For most therapies, evidence is insufficient to show benefit. There is strong evidence that secretin and facilitated communication are not effective. Some therapies, such as hyperbaric oxygen, chelation, and high dose vitamins, are potentially harmful. For children with restrictive diets, taking a daily multivitamin and 400 IU vitamin D may be indicated, although there is no evidence to support megadoses of vitamins. Similarly, for children with evidence of gluten sensitivity, a trial of a gluten free diet may be indicated. However, cur rent evidence does not support this as a treatment for all children with ASD. There is an interest in the use of cannabidiol (CBD) to treat core autism symptoms or co occurring problems such as anxiety, ADHD, or sleep problems, but there is currently no evidence to support this therapy. When discussing CAM with a family, it is best to use open and collaborative communication, encouraging them to share their cur rent practices and any questions. Specifically ask if they use any herbal treatments, supplements, or other therapies, such as acu puncture, massage, or chiropractic treatment, and what they have observed since trying the treatment. Provide accurate information regarding potential benefit and risk for any treatment. Educate about red flags such as treatments that are marketed as a cure for multiple conditions, that report no risk of side effects, or that are marketed by the clinician recommending the treatment. Encourage families to identify a target symptom, try one thing at a time, and monitor response carefully. Transition Navigating a successful transition to adult care is a key role for the pediatric provider. This process should ideally start as early as age 12 13 years. Parents are faced with a complex and disconnected sys tem of diverse agencies that they need to navigate. Use of structured visit templates and care coordinators can help ensure that families and their youth with ASD are able to make appropriate decisions about secondary and postsecondary educational programming, vocational training, guardianship, finances, housing, and medical care. High school educational programming should include indi vidualized and meaningful vocational training, as well as instruc tion regarding sexuality, relationships, safetyparticularly internet safety and abuse preventionfinances, travel training, and general self advocacy. More than half of young adults with ASD remain unemployed and unenrolled in higher education 2 years after high school graduation. Individuals with ASD who are of average cogni tive intellectual functioning will need help accessing supports for college or postsecondary skills training and may benefit from refer ral to their state vocational rehabilitative services and personal life coaches or counselors. Families who have adult children with more significant cognitive disability need information about the range of adult disability services; how to apply for supplemental security income (SSI); and the process for considering guardianship, medi cal and financial conservatorship, or supported decision making for their adult child. These decisions are complex and must be
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indi vidualized for the adult with ASD and the family. OUTCOME ASD is a lifelong condition. Although a minority of individuals no longer meet criteria for the diagnosis, most will make progress but continue to have some impairment in social, behavioral, learning, language, or emotional functioning as adults. Adult outcome stud ies are sobering, indicating that many adults with ASD are socially isolated, lack gainful employment or independent living, and have higher rates of depression and anxiety. It is not clear if these data can be extrapolated to younger children currently receiving inten sive educational therapies. There is a growing network of adult self advocates who promote the unique strengths in individuals with ASD. Outcome, as measured by developmental progress and functional independence, is better for individuals who have higher cognitive and language skills and lower ASD severity at initial diagnosis. Visit Elsevier eBooks at eBooks.Health.Elsevier.com for Bibliography Fragile X syndrome (FXS) is a genetic disorder associated with intellectual, learning, and behavioral symptoms and some specific physical characteristics. In FXS an expansion of 200 CGG repeats on the distal long arm of chromosome Xq27.3 silences the FMR1 gene, which leads to a deficiency in fragile X mental retardation protein (FMRP) and affects synaptic function throughout much of the brain. It is the most common heritable cause of intellectual dis ability and has a prevalence rate of approximately 1 in 4,000 males and 1 in 7,000 females. Like many X linked disorders, males with fragile X tend to present with more features and more significant impairments than females. On average, unaffected individuals have 30 CGG repeats in the untranslated region of the FMR1 gene. Those with 55 200 repeats are described as having the premutation. Females with the premutation are at increased risk of expansion of the number of CGG repeats causing FXS in their children (Table 59.1). When males with the premutation alleles pass them to daughters, they typically remain as premutation alleles. Those with premutation alleles may also have clinical manifes tations (Tables 59.2 and 59.3). Fragile XE syndrome (FRAXE) resembles FXS and manifests within a variable spectrum of intellectual and learning disabilities. The involved gene (AFF2) results in an expansion of CCG trinucleo tide repeats and is inherited as an X linked disorder. Symptoms also include aggressive behaviors, agitation, autistic behaviors, clumsi ness, and delayed speech and language development. This form of FXS will not usually be detected with standard fragile X testing. EVALUATION AND DIAGNOSIS The phenotype of FXS early in life can be nonspecific with symp toms such as developmental delay, including motor and language delays, and autistic like behaviors, such as repetitive motor man nerisms, sensory sensitivities, and deficits in eye contact. Mani festations in early to middle childhood often include problems with learning, attention deficithyperactivity disorder (ADHD), anxiety, and aggressive behaviors. The physical features become more pronounced during or after puberty and include macro orchidism, hyperextensible finger joints, and characteristic facial features, including a long face, large ears, and a prominent square jaw (Fig.
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59.1). Females affected with FXS show varying degrees of intellectual disability andor learning disabilities, and they may present with symptoms of ADHD and anxiety as well. Children with FXS are at increased risk for ophthalmologic, feed ing, and orthopedic problems, as well as recurrent otitis media in early childhood. Females are at increased risk for precocious puberty. Chapter 59 Fragile X Syndromes Amanda E. Bennett and Marcy Schuster Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 384 Part IV u Learning and Developmental Disorders Table 59.1 Risk of Expansion of a Premutation to a Full Mutation in Male Offspring Based on Maternal Number of CGG Triplet Repeats MATERNAL CGG TRIPLET REPEAT NUMBER RISK FOR EXPANSION OF PREMUTATION TO FULL MUTATION 59 69 37 70 79 65 80 89 70 90 99 95 100 or more 100 CGG triplet repeat, Cytosine guanine guanine trinucleotide repeat. From Fragile X Syndrome. Clinical Overview. Elsevier Point of Care. https:www.clinica lkey.com!contentclinicaloverview67 s2.0 c9588237 6031 4f21 b273 34970f89cd2e. Updated June 14, 2021. Copyright Elsevier. All rights reserved; with data from Hersh JH et al. Health supervision for children with fragile X syndrome. Pediatrics. 2011;127(5):9941006, Table 1; and Saul RA et al. FMR1 related disorders. In: Pagon RA et al, eds. GeneReviews internet. University of Washington; 19932018. Table 59.2 Phenotypic and Genetic Effect of Number of CGG Repeats VARIATION TYPE CGG ALLELE SIZE TYPICAL PHENOTYPE GENETIC CONSEQUENCES Full mutation More than 200 repeats Males are affected with fragile X syndrome About 50 of females are affected with fragile X syndrome Repeat expansion and methylation typically result in partial or complete silencing of FMR1 Females usually benefit from having two X chromosomes, because usually one of them is unaffected (i.e., no expanded CGG repeats) and X inactivation does not silence all copies of it Premutation About 55 200 repeats Patients typically have normal intellect, and some may have mild manifestations associated with fragile X syndrome Carriers may be at increased risk for fragile Xassociated tremor ataxia syndrome and FMR1 related primary ovarian insufficiency FMRP expression is usually not significantly impaired; however, larger mutations may have lowered expression Alleles are at risk for CGG expansion during maternal gametogenesis, and offspring are at risk for fragile X syndrome Intermediate (gray zone) About 45 54 repeats Patient does not have fragile X syndrome caused by CGG repeats A minority of intermediategray zone alleles may have minor instability; however, expansion of CGG repeats is unlikely, and if it occurs, it will not reach full mutation number within a single generation Normal About 5 44 repeats Patient does not have fragile X syndrome caused by CGG repeats No meiotic or mitotic instability is present; alleles are transmitted without any change in repeat number FMR1 gene, FMRP translational regulator 1; FMRP, fragile X mental retardation protein. From Fragile X Syndrome. Clinical Overview. Elsevier Point of Care. https:www.clinicalkey.com!contentclinicaloverview67 s2.0
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c9588237 6031 4f21 b273 34970f89cd2e. Updated June 14, 2021. Copyright Elsevier. All rights reserved; with data from Hersh JH et al. Health supervision for children with fragile X syndrome. Pediatrics. 2011;127(5):9941006, Table 1; and Saul RA et al. FMR1 related disorders. In: Pagon RA et al, eds. GeneReviews internet. University of Washington; 19932018. Adolescents should be monitored for seizures and heart murmurs, and adults with FXS are at increased risk for mitral valve prolapse. Adults are also at risk for intention tremor and ataxia and premature meno pause, which can also occur in those with the premutation. Table 59.3 includes phenotypic features, clinical signs, and their typical age of onset. Family History and Premutation Carriers Collecting a detailed family history can help identify potential risk factors for FXS. Individuals with premutation triplet repeat expan sions have been found to have a variety of clinical manifestations. Fragile Xassociated tremorataxia syndrome (FXTAS) is a pro gressive neurodegenerative disorder that most commonly affects males over age 50 years. Females are less commonly affected and tend to have mild disease. Symptoms include an intention tremor followed by ataxia that may manifest as needing support when walking or with a wide based gait. Females with premutation tri ple repeat expansions are at risk for developing fragile Xassoci ated premature ovarian insufficiency (FXPOI). Women with this condition undergo menopause approximately 5 years earlier than women without the condition, but symptoms are variable, with the most severely affected experiencing irregular or absent menstrual periods before age 40 and often infertility. A variety of neuropsychi atric symptoms, including anxiety, ADHD, social deficits, or autism spectrum disorder (ASD), have also been associated with the pre mutation. Asking about family members for a history of develop mental, behavioral, or learning problems or adult family members with early menopause, fertility challenges, or adult onset neuro logic problems may help to identify risk for a positive fragile X test in a child with developmental or behavioral concerns. Asymptom atic siblings or other family members may benefit from testing to determine premutation status, which can also be associated with the symptoms noted earlier. See Table 59.3 for additional information about clinical symptoms in premutation carriers. Diagnostic Testing A diagnosis of FXS is possible through PCR and Southern blot analysis of a patients blood. Positive DNA testing shows an expan sion of 200 trinucleotide CGG repeats inside an area of the FMR1 gene on the X chromosome. Diagnostic testing that reports meth ylation status of the gene region is preferred because methylation status is inversely correlated with cognitive functioning. Because the physical features of FXS are not always apparent in early child hood, diagnostic testing is recommended for any child who pres ents with global developmental delay, intellectual disability, or ASD (see Chapters 56 and 58). Any positive test for fragile X should include genetic counseling to inform of inheritance risk, pheno typic variability, and medical conditions associated with FXS and premutation status. Specific gene (AFF2) testing for FRAXE should be considered if CGG
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repeat testing is negative. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 59 u Fragile X Syndromes 385 MANAGEMENT OF FRAGILE X SYNDROME Management of FXS in children often requires a multidisciplinary approach focused on monitoring for and managing developmental andor behavioral symptoms. In addition to health supervision visits with a primary care clinician, many children with FXS benefit from ongoing care with a medical professional with experience or knowl edge of FXS. Families will also benefit from accessing educational and behavioral health resources in the community. Educational Many individuals with FXS will require educational support to meet their needs starting from a young age. Early intervention services, including speech therapy, occupational therapy, physical therapy, and special instruction, are often vital components of address ing developmental delays. As a child ages and ongoing assessment occurs, special education support through an individualized edu cation plan (IEP) may be warranted (See Chapter 49). There are interventions shown to be specific to the learning needs of indi viduals with FXS. Biologic males typically demonstrate strengths in receptive language, verbal labeling, simultaneous processing, imi tation, and daily living activities. Biologic females typically dem onstrate areas of strength in vocabulary, comprehension, reading, writing, spelling, and short term visual memory. These advantages should be explored when educational interventions are being devel oped. Areas often in need of interventions for individuals with FXS include improving complex problem solving, maintaining atten tion, improving impulse control, understanding spatial relation ships, and math concepts. Environmental modifications and adaptive technologies can be an asset for an individual with FXS. This can include a modified keyboard andor mouse and touch screen computer options inte grated into classroom lessons. A quiet environment with minimal distractions can help improve focus on tasks. Small group and one on one instruction for teaching new tasks can minimize anxiety and improve generalization of skills to the larger classroom. Teaching students to request breaks when feeling overwhelmed can minimize overall frustration. Visual schedules, manipulatives, clutter free areas, and social stories are all interventions to improve compliance and learning. Behavioral Individuals with FXS can present with a variety of cognitive and behavioral challenges. ASD is diagnosed in between 50 and 60 of individuals with FXS. ASD is characterized by deficits in com munication and social skills along with restricted interests andor repetitive behaviors that interfere with ones daily life (see Chapter 58). Individuals with FXS can struggle with making eye contact, engaging in conversations, and expressing wants and needs. Often individuals with FXS want social contact but may avoid it due to anxiety. Hyperarousal is a common behavioral symptom, particu larly in social situations where eye contact is expected, suggesting the presence of significant sensory aversions. Behavioral interven tions that include skill development and anxiety management can be helpful in addressing social skills deficits. Other sensory aversive behaviors can be related to
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auditory, visual, or tactile stimuli. Tan trums, and occasionally aggression, can emerge when children with FXS are overstimulated. Sensory seeking behaviors can also be present in individuals with FXS. These may include repetitive movements, narrowed interests, rigid routines, and atypical sensory exploration. Behaviors such as rocking, pacing, and jumping could occur to obtain sensory input. Individuals with FXS can become extremely anxious if a routine is changed or if a preferred activity is interrupted. Teaching coping strat egies along with the recognition of triggers for anxiety can be helpful as a behavior management strategy. Individuals with FXS can present with deficits in attention and focus, impulsivity, andor hyperactivity, particularly during child hood. This can lead to a diagnosis of ADHD (see Chapter 50). These deficits can affect learning in school and require specialized Table 59.3 Clinical Features of Fragile X Syndrome and Premutation Carriers COGNITIVE, BEHAVIORAL, AND PHYSICAL CHARACTERISTICS AGE REPORTED FULL MUTATION FRAGILE X SYNDROME (200 CGG REPEATS) Hypotonia Infancy Reflux Infancy Poor suck Infancy Developmental delayintellectual disability (96 males, 64 females) Early childhood Autism (46 males, 16 females) Early childhood Attention problems (84 males, 67 females) Early childhood Hyperactivity (66 males, 30 females) Early childhood Anxiety (70 males, 56 females) Early childhood Aggression (38 males, 14 females) Early childhood Self injurious behaviors (41 males, 10 females) Early childhood Depression (12 males, 22 females) Early childhood Recurrent otitis media (60) Early childhood Seizures (18 males, 7 females) Early childhood Strabismus (20) Early childhood Sleep disturbances Early childhood Flat feet Early childhood Low muscle tone Early childhood Hyperextensible joints Early childhood Large prominent ears Earlymiddle childhood Elongated face Earlymiddle childhood Large testes Adolescence Obesity (30) Adolescence Mitral valve prolapse Adulthood Cognitive declineparkinsonism (17) Adulthood Perseveration Adulthood PREMUTATION CARRIERS (55 200 CGG REPEATS) Attention problems Early childhood Autism spectrum disorder Early childhood Seizures Early childhood Anxiety Adolescence Depression Adulthood Hypertension Adulthood Sleep disturbances Adulthood Migraine Adulthood Fibromyalgia Adulthood Hypothyroidism Adulthood Fragile Xassociated primary ovarian insufficiency (FXPOI) (20) Adulthood Fragile Xassociated tremor ataxia syndrome (FXTAS) (40 males, 16 females) Later adulthood Data from National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention. Data and Statistics on Fragile X Syndrome, 2021; Hagerman RJ, Berry Kravis E, Hazlett HC, et al. Fragile X syndrome. Nat Rev Dis Primers. 2017;3:17065; Hersh JH, Saul RA; Committee on Genetics. Health supervision for children with fragile X syndrome. Pediatrics. 2011;127(5):9941006; Wheeler A, Raspa M, Hagerman R, Mailick M, Riley C. Implications of the FMR1 Premutation for Children, Adolescents, Adults, and Their Families. Pediatrics. 2017;139(Suppl 3):S172S182. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 386 Part IV u Learning and Developmental Disorders instruction or classroom accommodations to help improve focus and participation. Individuals with FXS can present with aggressive behavior directed toward themselves and toward others. These behaviors are seen in approximately 50 of males with FXS and
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tend to increase with age. Individuals who exhibit ongoing aggression also typically present with more significant intellectual impairment, communication delays, and anxiety. Aggression can put a strain on caregivers or lead to injury and therefore often emerges as a primary focus of treatment. Behavior management techniques vary depending on a childs needs. If an ASD diagnosis is present, applied behavioral analysis (ABA) pro grams are often integrated into treatment. ABA promotes multiple areas of development, including language, emotion, and cognition. ABA focuses on tracking specific behaviors through observation and data collection, learning their antecedents (the event or environment before the behavior occurred), and managing their consequences (the response others have after the behavior occurs) through a structured approach. Most interventions for unwanted behaviors (e.g., aggression or self injury) aim to change the antecedents to reduce the likelihood of the behavior occurring or to change the consequence in order to make the behavior less rewarding for the individual. Interventions that aim to increase a desired behavior (e.g., complying with an instruction or toilet training) will incorporate environmental changes to remind and encourage the behavior and identify rewarding consequences that can be delivered after the behavior has occurred. ABA interventions delivered during daily living activities, community participation, and family interactions allow for optimal skill development. Special educa tion programs often include similar behavior management techniques throughout the early childhood for individuals with FXS. Medical In addition to educational and behavioral management, many chil dren with FXS may present with certain medical conditions and may require additional monitoring or care by a specialist (see Table 59.3). Monitoring in infancy and early childhood should empha size assessment for orthopedic, growth, andor feeding concerns. Because young children with FXS are more susceptible to otitis media and may lack communication skills to convey discomfort, a full physical examination, including ear examination, is recom mended if a child presents with acute behavior changes. Young children should also be routinely screened for ophthalmologic problems, such as strabismus or astigmatism, and monitored for symptoms related to connective tissue problems, such as hypermo bile joints or inguinal hernias. Seizures are more prevalent in chil dren with FXS; symptoms concerning for any type of seizure should be investigated with electroencephalogram (EEG) when the child is both awake and asleep. Although risk for mitral valve prolapse is not typically increased until adulthood, examination for murmurs, clicks, or changes in blood pressure should be performed regularly. Sleep disturbances commonly reported among children with FXS include delayed sleep onset, frequent night waking, and occasion ally obstructive sleep apnea. Screening for sleep concerns should be done at every visit, and parents should be counseled on behavioral strategies to address sleep onset and waking challenges (see Chapter 31). Concerns for apnea or snoring may require further evaluation by a sleep specialist or with polysomnography. Medications to help address sleep concerns may include melatonin or clonidine, neither of which is currently approved by the Food and Drug Administra tion (FDA) for use in children with FXS. There
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are currently no approved treatments for the core symp toms of FXS, but many individuals will benefit from medication to address some of the commonly co occurring behavioral symptoms associated with absence of FMRP. If behavioral strategies are not sufficient to address hyperactivity or impulsivity, a young child (5 years) may benefit from a trial of an 2 adrenergic agonist, such as clonidine or guanfacine. School aged children with FXS often show improvements in hyperactivity, impulsivity, andor attention problems when treated with a stimulant, but side effects such as irritability or aggression may occur. Selective serotonin reuptake inhibitors (SSRIs) can be safe and effective in reducing anxiety, obsessive compulsive symptoms, and sometimes aggression in young children with FXS; one trial of sertraline in young children with FXS demonstrated improvements in visual reception and fine motor coordination in 2 to 6 year olds. Additional analyses dem onstrated improvements in expressive language skills for children with FXS and ASD. Treatment with an atypical antipsychotic, such as risperidone or aripiprazole, may be needed in cases of severe anxiety, aggression, or mood instability that have not responded to other medications. Neurobiologic studies of FXS have identified overactivation of brain glutamate pathways and underactivation of gamma aminobutyric acid (GABA) pathways leading to studies of A B C Fig. 59.1 Boys with fragile X syndrome. Note the long faces, prominent jaws, and large ears and the similar characteristics of children from different ethnic groups: European (A), Asian (B), and Latin American (C). (From Jorde, LB, Carey JC, Bamshad MJ. Medical Genetics, 6th ed. Philadelphia: Elsevier; 2020: Fig. 5.20.) Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 59 u Fragile X Syndromes 387 medications targeting these pathways in the hopes that they would improve cognitive outcomes. Although some studies in animal models were encouraging, human trials have yet to demonstrate consistent benefits. Some clinical trials are ongoing. In addition to continued monitoring for cardiac, seizure, sleep, and behavioral symptoms, health supervision in late childhood and adolescence should also include discussion of adult transition issues, including vocational training, accessing state specific adult disability services, and transition to adult medical care. Visit Elsevier eBooks at eBooks.Health.Elsevier.com for Bibliography. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 388 PART VNutrition Nutrition for infants, children, and adolescents should maintain cur rent weight and support normal growth and development. Growth during infancy is rapid, critical for neurocognitive development, and has the highest energy and nutrient requirements relative to body size compared with any other period of growth. It is followed by growth during childhood, when 60 of total growth occurs, and finally by puberty. Nutrition and growth during the first 3 years of life pre dict adult stature and
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some health outcomes. Although the anteced ents are numerous and occur earlier, the major risk period for linear growth faltering or stunting (length or height for age z score 2) is between 6 and 24 months of age. Therefore it is critical to identify nutrient deficiencies promptly and to address them aggressively early in life, because missing them can impart lasting adverse effects on later growth and development. Dietary intake should meet energy requirements, as well as provide the essential macronutrients and micronutrients needed for sustain ing the function of multiple vital processes. Nutrient deficiencies can limit growth, impair immune function, affect neurodevelopment, and increase morbidity and mortality. Worldwide, malnutrition and under nutrition are the leading causes of acquired immunodeficiency and a major factor underlying morbidity and mortality in children 5 years of age. The transition in food supply and the type of nutrition chosen in many developing countries from a traditional to Western diet has resulted in increased life expectancy and adult stature. It is associated with decreases in the incidence of communicable diseases. Unfortu nately, the Western diet, characterized by high energy density, more refined grains, and highly processed foods, is also frequently accompa nied by decreased physical activity and increases in the incidence and prevalence of noncommunicable diseases such as type 2 diabetes, car diovascular (CV) disease, obesity, inflammatory bowel disease (IBD), and certain cancers. Consequently, it is important to view the impact of diet and nutrition on health from various perspectives: to prevent deficiency, to promote adequacy, and to prevent or reduce the risk for acquiring diseases associated with excess intakes, such as obesity, dia betes, and CV disease. Advances in our understanding of the roles of some nutrients such as vitamin D, polyunsaturated fatty acids (PUFAs), and fiber have changed our focus from recommendations about preventing deficiency to recommendations about nutritional intake associated with optimal health. The 2006 World Health Organization (WHO) growth charts, recommended for all infants and children until age 2 years, are not only descriptive but also prescriptive on how children with adequate nutri tion and healthcare should grow. Identifying and providing appropri ate and adequate nutrition in infancy and childhood are critical to supporting normal growth and development, as well as providing the foundation for lifelong health and well being. DIETARY REFERENCE INTAKES The dietary reference intakes (DRI) were established by the Food and Nutrition Board of the U.S. Institute of Medicine (IOM), currently known as the National Academy of Medicine (NAM), to provide guid ance on the nutrient needs for individuals and groups across different life stages and according to gender (Tables 60.1 60.3 and see Tables 60.5 and 60.6). The DRI represent a series of indicators that are used as a basis for macronutrient and micronutrient intake recommendations for healthy populations within the United States and Canada. The DRI also serve as an estimation of the Dietary Guidelines for Americans 2020 2025 (DGA) Daily Nutritional Goals. DRI indicators include the estimated Chapter 60 Nutritional Requirements Martine Saint Cyr, Stephanie
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W. Waldrop, and Nancy F. Krebs Table 60.1 Equations to Estimate Energy Requirements INFANTS AND YOUNG CHILDREN: EER (KCALDAY) TEE ED 0 3 mo EER (89 weight kg 100) 175 4 6 mo EER (89 weight kg 100) 56 7 12 mo EER (89 weight kg 100) 22 13 36 mo EER (89 weight kg 100) 20 CHILDREN AND ADOLESCENTS 3 18 YR: EER (KCALDAY) TEE ED BOYS 3 8 yr EER 88.5 (61.9 age yr PA (26.7 weight kg (903 height m) 20 9 18 yr EER 88.5 (61.9 age yr PA (26.7 weight kg (903 height m) 25 GIRLS 3 8 yr EER 135.3 (30.8 age yr PA (10 weight kg (934 height m) 20 9 18 yr EER 135.3 (30.8 age yr PA (10 weight kg (934 height m) 25 EER, Estimated energy requirement; TEE, total energy expenditure; ED, energy deposition (energy required for growth new tissue accretion). PA indicates the physical activity coefficient: For boys: PA 1.00 (sedentary, estimated physical activity level 1.0 1.4); PA 1.13 (low active, estimated physical activity level 1.4 1.6); PA 1.26 (active, estimated physical activity level 1.6 1.9); PA 1.42 (very active, estimated physical activity level 1.9 2.5) For girls: PA 1.00 (sedentary, estimated physical activity level 1.0 1.4); PA 1.16 (low active, estimated physical activity level 1.4 1.6); PA 1.31 (active, estimated physical activity level 1.6 1.9); PA 1.56 (very active, estimated physical activity level 1.9 2.5) Adapted from Kleinman RE (ed). Pediatric Nutrition Handbook, 7th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2013. Table 60.2 Acceptable Macronutrient Distribution Ranges AMDA ( OF ENERGY) MACRONUTRIENT AGE 1 3 YR AGE 4 18 YR Fat 30 40 25 35 6 PUFAs (linoleic acid) 5 10 5 10 3 PUFAs ( linolenic acid) 0.6 1.2 0.6 1.2 Carbohydrate 45 65 45 65 Protein 5 20 10 30 PUFAs, Polyunsaturated fatty acids. Adapted from Otten JJ, Hellwig JP, Meyers LD (eds). Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: Institute of Medicine, National Academies Press; 2006. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 60 u Nutritional Requirements 389 Table 60.3 Dietary Reference Intakes: Macronutrients FUNCTION LIFE STAGE GROUP RDA OR AI (gday) SELECTED FOOD SOURCES ADVERSE EFFECTS OF EXCESSIVE CONSUMPTION TOTAL DIGESTIBLE CARBOHYDRATE RDA based on its role as the primary energy source for the brain AMDR based on its role as a source of kcal to maintain body weight Infants Major types: starches and sugars, grains, and vegetables (corn, pasta, rice, potatoes, and breads) are sources of starch. Natural sugars are found in fruits and juices. Sources of added sugars: soft drinks, candy, fruit drinks, desserts, syrups, and sweeteners. No defined intake level for potential adverse effects of total digestible carbohydrate is identified, but the upper end of the AMDR was based on decreasing risk of chronic disease and
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providing adequate intake of other nutrients. It is suggested that the maximal intake of added sugars be limited to providing no more than 10 of energy. 0 6 mo 60 7 12 mo 95 Children 1 yr 130 Pregnancy 18 yr 175 19 30 yr 175 TOTAL FIBER Improves laxation, reduces risk of coronary artery (heart) disease, assists in maintaining normal blood glucose levels Infants Includes dietary fiber naturally present in grains (e.g., oats, wheat, unmilled rice) and functional fiber synthesized or isolated from plants or animals and shown to be of benefit to health. Dietary fiber can have variable compositions; therefore it is difficult to link a specific source of fiber with a particular adverse effect, especially when phytate is also present in the natural fiber source. As part of an overall healthy diet, a high intake of dietary fiber will not produce deleterious effects in healthy persons. Occasional adverse GI symptoms are observed when consuming some isolated or synthetic fibers, but serious chronic adverse effects have not been observed because of the bulky nature of fibers. Excess consumption is likely to be self limiting; therefore UL was not set for individual functional fibers. 0 6 mo ND 7 12 mo ND Children 1 3 yr 19 4 8 yr 25 Males 9 13 yr 31 14 18 yr 38 19 21 yr 38 Females 9 13 yr 26 14 18 yr 26 19 21 yr 25 Pregnancy 18 yr 28 19 21 yr 28 TOTAL FAT Energy source When found in foods, is a source of 3 and 6 PUFAs Facilitates absorption of fat soluble vitamins Infants Infants: Human milk or infant formula Older children: Butter, margarine, vegetable oils, whole milk, visible fat on meat and poultry products, invisible fat in fish, shellfish, some plant products such as seeds and nuts, bakery products. UL is not set because there is no defined intake of fat at which adverse effects occur. High fat intake will lead to obesity. Upper end of AMDR is also based on reducing risk of chronic disease and providing adequate intake of other nutrients. Low fat intake (with high carbohydrate) has been shown to increase plasma triacyl glycerol concentrations and decrease HDL cholesterol. 0 6 mo 31 7 12 mo 1 18 yr 30 Insufficient evidence to determine AI or EAR; see AMDR, Table 60.2. 6 POLYUNSATURATED FATTY ACIDS Essential component of structural membrane lipids, involved with cell signaling Precursor of eicosanoids Required for normal skin function Infants Nuts, seeds; vegetable oils such as soybean, safflower, corn oil. There is no defined intake of 6 level at which adverse effects occur. Upper end of AMDR is based on the lack of evidence that demonstrates long term safety and human in vitro studies that show increased free radical formation and lipid peroxidation with higher amounts of 6 fatty acids. Lipid peroxidation is thought to be a component of atherosclerotic plaques. 0 6 mo 4.4 7 12 mo 4.6 Children 1 3 yr 7 4 8 yr
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10 Males 9 13 yr 12 14 18 yr 16 19 21 yr 17 Females 9 13 yr 10 14 18 yr 11 19 21 yr 12 Pregnancy 18 yr 13 19 21 yr 13 Lactation 18 yr 13 19 21 yr 13 Continued Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 390 Part V u Nutrition Table 60.3 Dietary Reference Intakes: Macronutrientscontd FUNCTION LIFE STAGE GROUP RDA OR AI (gday) SELECTED FOOD SOURCES ADVERSE EFFECTS OF EXCESSIVE CONSUMPTION 3 POLYUNSATURATED FATTY ACIDS Involved with neurologic development and growth Precursor of eicosanoids Infants Vegetable oils (e.g., soybean, canola, flaxseed oil); fish oils, fatty fish, walnuts; smaller amounts in meats and eggs. No defined intake levels for potential adverse effects of 3 PUFAs are identified. Upper end of AMDR is based on maintaining appropriate balance with 6 fatty acids and the lack of evidence that demonstrates long term safety, along with human in vitro studies that show increased free radical formation and lipid peroxidation with higher amounts of PUFAs. Because the longer chain n 3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are biologically more potent than their precursor, linolenic acid, much of the work on adverse effects of this group of fatty acids has been on DHA and EPA. Lipid peroxidation is thought to be a component in the development of atherosclerotic plaques. 0 6 mo 0.5 7 12 mo 0.5 Children 1 3 yr 0.7 4 8 yr 0.9 Males 9 13 yr 1.2 14 18 yr 1.6 19 21 yr 1.6 Females 9 13 yr 1.0 14 18 yr 1.1 19 21 yr 1.1 Pregnancy 18 yr 1.4 19 21 yr 1.4 Lactation 18 yr 1.3 19 21 yr 1.3 SATURATED AND TRANS FATTY ACIDS The body can synthesize its needs for saturated fatty acids from other sources. No dietary requirement Saturated fatty acids are present in animal fats (meat fats and butter fat) and coconut and palm kernel oils. Trans fat: stick margarines, foods containing hydrogenated or partially hydrogenated vegetable shortenings There is an incremental increase in plasma total and LDL cholesterol concentrations with increased intake of saturated or trans fatty acids; therefore saturated fat intake should be limited to 10 with no trans fat. CHOLESTEROL No dietary requirement Sources: liver, eggs, foods that contain eggs (e.g., cheesecake, custard pie) PROTEIN AND AMINO ACIDS Major structural component of all cells in the body Functions as enzymes, in membranes, as transport carriers, and as some hormones During digestion and absorption, dietary protein is broken down to amino acids, which become the building blocks of these structural and functional compounds Nine indispensable amino acids must be provided in the diet; the body can make the other amino acids needed to synthesize specific structures from other amino acids Infants Proteins from animal sources (e.g., meat, poultry, fish, eggs, milk, cheese, yogurt) provide
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all nine indispensable amino acids in adequate amounts and are considered complete proteins. Protein from plants, legumes, grains, nuts, seeds, and vegetables tend to be deficient in 1 of the indispensable amino acids and are called incomplete proteins. Vegan diets adequate in total protein content can be made complete by combining sources of incomplete protein, which lack different indispensable amino acids. No defined intake levels for potential adverse effects of protein are identified. Upper end of AMDR was based on complementing AMDR for carbohydrate and fat for the various age groups. Lower end of AMDR is set at approximately the RDA. 0 6 mo 9.1 7 12 mo 11.0 Children 1 3 yr 13 4 8 yr 19 Males 9 13 yr 34 14 18 yr 52 19 yr 56 Females 9 13 yr 34 14 yr 46 18 yr 19 21 yr Pregnancy and lactation 46 71 Note: Starred () numbers are Adequate Intake (AI) bold numbers are RDA. RDAs and AIs may both be used as goals for individual intake. RDAs are set to meet the needs of 9798 of members in a group. For healthy breastfed infants, the AI is the mean intake. The AI for other life stage and gender groups is believed to cover the needs of all members of the group, but lack of data prevents specifying with confidence the percentage covered by this intake. AMDR is the range of intake for a particular energy source that is associated with reduced risk of chronic disease while providing intakes of essential nutrients. With consumption in excess of the AMDR, there is a potential for increasing the risk of chronic diseases andor insufficient intakes of essential nutrients. ND amounts are not determinable because of a lack of data regarding adverse effects in this age group and concern with regard to a lack of ability to handle excess amounts. Source of intake should be from food only to prevent high levels of intake. 20152020 Dietary Guidelines for Americans. U.S. Department of Health and Human Services. https:health.govdietaryguidelines2015. Based on 1.5 gkgday for infants, 1.1 gkgday for 1 3 yr, 0.95 gkgday for 4 13 yr, 0.85 gkgday for 14 18 yr, 0.8 gkgday for adults, and 1.1 gkgday for pregnant (using pre pregnancy weight) and lactating women. AI, Adequate intake; AMDR, acceptable macronutrient distribution range; EAR, estimated average requirement; GI, gastrointestinal; HDL, high density lipoprotein; LDL, low density lipoprotein; ND, not determinable; PUFAs, polyunsaturated fatty acids; RDA, recommended dietary allowance; UL, upper limit of normal. Institute of Medicine. 2005. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. https:doi.org10.1722610490. Adapted and reproduced with permission from the National Academy of Sciences, Courtesy of the National Academies Press, Washington, DC. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 60 u Nutritional Requirements 391 average requirement (EAR), the
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recommended dietary allowance (RDA), and the tolerable upper limit of intake (UL) (Figs. 60.1 and 60.2). In addition, the concept of the DRI is also applicable to the esti mated energy requirement (EER) and the acceptable macronutrient distribution range (AMDR). The EAR is an estimated average of the daily nutrient intake required to meet the nutritional needs of 50 of the population; it is applied to the assessment of a populations intake. The RDA provides an esti mate of the minimum daily average intake for a nutrient that meets the nutritional needs for more than 97 of individuals in a population, and it can be used as a guideline for individuals to avoid deficiency. When an EAR cannot be derived, an RDA cannot be calculated; therefore an adequate intake (AI) is developed as a guideline for individuals based on the best available data and scientific consensus. The UL denotes the highest average daily intake with no associated adverse health effects for almost all individuals in a given population. Figure 60.2 shows the relationships among EAR, RDA, and UL. ENERGY Energy balance constitutes both caloric intake, most often derived from food, and metabolic caloric expenditure. An imbalance between energy intake and energy expenditure can lead to undesirable health consequences. Inadequate energy intake can lead to weight faltering, catabolism of body tissues (e.g., fat and muscle), diminished immu nity, and increased morbidity and mortality. For infants, children, and adolescents, acute or chronic energy deficits can adversely affect motor, cognitive, and behavioral development. Excess energy intake can increase the risk for obesity and obesity related metabolic disease. Energy balance in adults is associated with maintenance of weight sta tus. Positive energy balance is required in children to support growth. Components of energy expenditure in adults include the basal meta bolic rate (BMR), which is primarily determined by lean body mass; the thermal effect of food (e.g., energy required for digestion and absorp tion); energy for thermoregulation; and energy for physical activity. Energy needs are increased during infancy, childhood, pregnancy, and lactation, necessitating increased energy intakes during these life stages. The 20202025 DGA provides important nutrition and health top ics applicable to each life stage, including data on estimates of caloric intake for healthy persons. The exact daily caloric requirement varies according to an individuals age, gender, height, weight, and physical activity, among other factors. Weight loss, weight maintenance, and weight gain depend on calories consumed and calories expended in the context of caloric needs. The estimated energy requirement (EER) for infants, children, and adolescents is the average dietary energy intake predicted to maintain energy balance, ensure adequate growth and development, and provide for a desirable level of physical activity. It considers age, gender, weight, stature, and level of physical activity (see Table 60.1). The EER was determined based on empirical research in healthy persons at different levels of physical activity and is estimated by equations that account for both total energy expenditure (TEE) and energy deposition (ED) for healthy growth. EERs for infants,
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relative to body weight, are approxi mately twice those for adults because of the increased metabolic rate and energy requirements for weight maintenance and growth. The EER was not devised for, and does not necessarily apply to, children with acute or chronic diseases who may have altered energy requirements due to chronic infection or inflammation, malabsorp tion, febrile illnesses, chronic lung disease, congenital heart disease, or other conditions. In these situations, energy requirements are typically higher when compared with healthy matched peers. Con versely, in some conditions, individuals may be hypometabolic and thus require less energy than expected (e.g., hypothyroidism, hypo thalamic obesity conditions, Down syndrome, and certain syndromic or monogenic obesity disorders). Individual energy needs for healthy persons based on age, gender, height, weight, activity level, preg nancy, or lactation status can be approximated using online tools, such as the DRI Calculator for Healthcare Professionals, available at https:www.nal.usda.govhuman nutrition and food safetydri calculator. Dietary nutrients that provide energy include fats (approximately 9 kcalg), carbohydrates (4 kcalg), and protein (4 kcalg). These nutri ents are called macronutrients. If alcohol is consumed, it also contrib utes to energy intake (7 kcalg). The EER does not specify the relative energy contributions of macronutrients. Once the minimal intake of each macronutrient is attained (e.g., sufficient protein intake to meet specific amino acid requirements, sufficient fat intake to meet linoleic acid and linolenic acid needs for brain development), the remainder of the intake is used to meet energy requirements, with some degree of freedom and interchangeability among fat, carbohydrate, and protein. This forms the basis for the acceptable macronutrient distribution ranges (AMDRs), expressed as a function of total energy intake (see Table 60.2). FAT Fat is the most calorically dense macronutrient, providing approxi mately 9 kcalg. For infants, human milk and formula are the main dietary sources of fat, whereas older children obtain fat from animal products, vegetable oils, margarine, and nuts and seeds. The AMDR for fats is 3040 of total energy intake for children 1 3 years and 2535 for children 4 18 years of age. In addition to being energy dense, lip ids provide essential fatty acids that have structural and functional roles (e.g., cholesterol moieties are precursors for cell membranes, hormones, and bile acids). Fat intake also facilitates absorption of fat soluble vitamins (vitamins A, D, E, and K). Both roles are relevant to neurologic and ocular development (see Table 60.3). Percentile rank 2.5 16 50 Median Mean 0 2.5 13.5 34 34 13.5 2.5 ?3 SD ?2 SD ?1 SD ?1 SD ?2 SD ?3 SD EAR RDA 50 50 84 97.5 Fig. 60.1 Dietary reference intakes. Normal requirement distribution of hypothetical nutrient showing percentile rank and placement of the estimated average requirement (EAR) and the recommended dietary allowance (RDA) on the distribution; SD, standard deviation. EAR R is k of in ad eq ua cy R isk of adverse effects RDA UL Observed level of intake 1.0 0.50.5 0.00.0 Fig. 60.2 Dietary reference intakes: The relationship among the
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es timated average requirement (EAR), the recommended dietary allow ance (RDA), and the tolerable upper limit of intake (UL). This figure shows that the EAR is the intake at which the risk of inadequacy is esti mated to be 0.5 (50). The RDA is the intake at which the risk of inad equacy would be very small, only 0.02 0.03 (23). At intakes between the RDA and the UL, the risk of inadequacy and of excess are estimated to be close to 0.0. At intakes above the UL, the potential risk of adverse effects can increase. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 392 Part V u Nutrition Dietary fats include phospholipids; free fatty acids; monoglycerides, diglycerides, and triglycerides; and sterols. Triglycerides are the most common form of dietary fat and are composed of one glycerol mol ecule with three fatty acids. They are found in both animal and vegeta ble fats. In addition, simple sugars (i.e., refined grains and high sugar drinks) can be converted to triglycerides in the liver. In general, dietary fatty acids can be classified as saturated, unsaturated, and more specifi cally, as monounsaturated or polyunsaturated. Dietary saturated fatty acids, found primarily in animal fat and dairy products as well as some vegetable fats (e.g., coconut and palm oil), can be synthesized endog enously by the body and thus are not required in the diet. Medium chain triglycerides (e.g., MCT oil) are beneficial for those suffering from malabsorptive disorders resulting in steatorrhea because of their direct absorption from the gastrointestinal (GI) tract into the blood stream via the portal vein, bypassing the need for pancreatic and biliary secretory components. The dietary saturated fatty acids most com monly consumed include myristic (C14), palmitic (C16), and steric acid (C18). Trans fatty acids are a type of unsaturated fat having undergone hydrogenation that alters the configuration of its double bond(s). They are found primarily in processed foods such as margarines and short enings and are nonessential. A small amount of naturally occurring trans fats can be found in animal products and human breast milk. Monounsaturated fatty acids are typically found in certain plants and their derived oils (e.g., avocado oil, olive oil, canola) and in some ani mal fats. Because monounsaturated fatty acids can be synthesized by the liver, they are considered nonessential to the diet. Polyunsaturated fatty acids (PUFAs) are fatty acids not able to be synthesized de novo in the body and are necessary for maintenance of growth, skin integ rity, aspects of central nervous system development, and other essen tial physiologic functions such as regulation of gene transcription, immunity, and inflammation. These dietary essential fatty acids include linoleic (C18:2,W6,9) and linolenic acid (C18:3,W3,6,9), and they are discussed in more detail later. Neither monounsaturated nor polyunsaturated fatty acids contrib ute adversely to plasma cholesterol levels. However, dietary saturated fatty acids
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(found primarily in animal fat and dairy products), trans fats (found in hydrogenated margarines and oils), and cholesterol increase the low density lipoprotein (LDL) fraction of serum cholesterol, which is a risk factor for the development of atherosclerosis. Autopsy stud ies demonstrate that atherosclerosis begins early in childhood, even in infancy. Therefore dietary advice to optimize CV health should be given starting from age 2 years, when sufficient fat intake to sustain growth and brain development is less of a concern. It is recommended that saturated fat make up less than 10 of total daily calories in the diet for those age 2 years and above, with increased focus on con sumption of monounsaturated and polyunsaturated fats. Dietary trans fatty acids are to be avoided, particularly artificial trans fatty acids in the form of partially hydrogenated oils, which are no longer consid ered Generally Recognized as Safe (GRAS) by the U.S. Food and Drug Administration (FDA). Figure 60.3 shows the dietary contributions of saturated fat for those age 1 year and above. Because saturated and monounsaturated fats can be synthesized endogenously to support adequate structural and physiologic require ments, there is no AI or RDA set for these dietary components. Trans fats, which have no known health benefits in humans, also do not have an AI or RDA defined. A UL has not been set for cholesterol, saturated, or trans fats because there is a continuous positive linear association between intake of these fats and increased risk for CV disease, without a threshold level. Diets low in saturated fats without trans fats are there fore preferred. For optimal CV health in the general population, rather than limiting fat intake, advice should focus in most cases Other Sources 20 Higher Fat Milk Yogurt 6 Sandwiches 19 Desserts Sweet Snacks 11 Rice, Pasta Other GrainBased Mixed Dishes 7 Pizza 5 Vegetables, Excluding Starchy 4 Meat, Poultry Seafood Mixed Dishes 4 Chips, Crackers Savory Snacks 4 Poultry, Excluding Deli Mixed Dishes 4 Cheese 4 Eggs 3 Starchy Vegetables 3 Spreads 3 Meats, Excluding Deli Mixed Dishes 3 Within Sandwiches: Other Sandwiches 6 Burritos Tacos 4 Burgers 3 3 Chicken Turkey Sandwiches Breakfast Sandwiches Hotdog Sandwiches 2 1 Within Desserts Sweet Snacks: Ice Cream Frozen Dairy Desserts Cookies Brownies Doughnuts, Sweet Rolls Pastries Cakes Pies 4 3 2 2 Saturated Fat Average Intake: 239 caloriesday Fig. 60.3 Top sources and average intakes of saturated fat: U.S. population age 1 year and older. Estimates based on 2 day dietary intake data, weighted, from What We Eat in America (WWEIA), National Health and Nutrition Examination Survey (NHANES), 2013 2016. (From Dietary Guide lines for Americans. 2020 2025, Chapter 1: Nutrition and Health Across the Lifespan. Fig. 1.11. https:www.dietaryguidelines.govsitesdefaultfil es2020 12DietaryGuidelinesforAmericans2020 2025.pdf.) Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 60 u Nutritional Requirements 393 on changing the type of
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fat consumed. Because of their high energy density, excessive intake of all types of fatty acids has the potential to increase the risk of obesity. Humans are incapable of synthesizing the precursor 3 ( linolenic acid ALA) and 6 (linoleic acid LA) long chain PUFAs and depend on diet for these two essential fatty acids. Walnut, canola, and flaxseed oil are good sources of ALA. Good sources of LA include safflower and sunflower oil. Essential fatty acids are enzymatically elongated and desaturated into longer chain fatty acids (LC PUFAs) that serve essential physiologic roles in the body. ALA can be converted to eicosa pentaenoic acid (EPA) and docosahexaenoic acid (DHA). LA is con verted to arachidonic acid (ARA). The conversion of ALA to EPA and DHA and of LA to ARA is influenced by many factors, including type and amounts of dietary fats and by enzymatic substrate affinity among competing 3, 6, 9, saturated, and trans fatty acids. Approximately 0.5 of dietary ALA is converted to DHA, and 5 of ALA intake is converted to EPA; therefore dietary intake of LC PUFAs is an impor tant determinant of serum and tissue DHA and EPA status. LC PUFAs such as DHA and ARA have a variety of cellular struc tural and functional roles; they influence membrane fluidity and gene expression and modulate the inflammatory response. ARA and DHA are present in breast milk and reflect maternal intake. They are often supplemented in infant formulas and are important for optimal growth and development. DHA is highly concentrated in the retina and is involved in the visual evoked response in infants. Risk factors for essential fatty acid deficiency (i.e., deficiency of ALA and LA) include severe fat malabsorption, prematurity, and administration of fat free parenteral nutrition. Deficiency can develop within 2 4 weeks of inadequate intake. Essential fatty acid deficiency of LA is associated with desquamating skin rashes, alopecia, throm bocytopenia, impaired immunity, and growth deficits, but is rare in the general population. Deficiency of ALA has been associated with paresthesias, weakness, impaired gait, impaired vision, hemorrhagic folliculitis, and impaired wound healing. The biologic activity and health benefits of ALA are thought to be derived from its elongation products EPA and DHA. Consistent with the findings of limited conversion of ALA to EPA and DHA, the DRI stipulates that up to 10 of the AI for 3 PUFA (ALA being the major dietary constituent) can be replaced by DHA and EPA to support nor mal neural development and growth. The ratio of dietary intake of each type of PUFA influences their relative amounts in different tissue com partments. A dietary 6:3 PUFA ratio of 4 5:1 may be associated with improved health outcomes, compared with the current 15 30:1 ratio typically observed in U.S. diets. In general, 6 fatty acids tend to have more proinflammatory effects and 3 fatty acids more antiin flammatory effects, which have potential implications for adjunctive nutritional management of chronic inflammatory conditions. PROTEIN Protein and amino acids have structural
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and functional roles in every cell in the body. Dietary protein intake is required to maintain and replenish the turnover of protein and to meet amino acid needs for growth. Dietary protein also provides approximately 4 kcalg as an energy substrate when intake is in excess of needs or derived from endogenous sources during periods of catabolism. Inadequate energy intake or inadequate protein intake increases catabolism of body pro tein reservoirs (i.e., lean body mass) for energy and free amino acids required to support normal physiologic function. Without adequate daily dietary protein intake, endogenous sources will be mobilized at the expense of function. Negative energy balance (weight loss) is asso ciated with an obligatory negative nitrogen balance. Nitrogen from protein turnover is primarily excreted in urine and stool. Increased protein intake of up to 2030 may be required during hypermetabolic states, as well as in those infants and children recov ering from malnutrition. Certain conditions may require a modest increase in protein intake, including conditions with high protein turnover, such as cystic fibrosis, inflammatory conditions, critical ill nesses, extensive burn injuries, compensated liver disease, and post surgical states including bariatric surgery (e.g., laparoscopic sleeve gastrectomy and Roux en Y gastric bypass). Premature infants also require increased protein intakes due to increased needs related to accelerated growth rates. In addition, athletes engaging in resistance, muscle building training may have increased total protein needs of approximately 1.2 2.0 gkgday to prevent loss of lean body mass and to maintain nitrogen balance. Importantly, the increased pro tein intake in these situations must occur in the context of adequate energy intake in order for protein deposition to occur, thus ensur ing that protein is not used or catabolized for energy. Moderate to severe protein energy malnutrition (PEM), although relatively rare in the noninstitutionalized U.S. population, is more common in low resource settings. Mild PEM occurs more commonly in the United States, leading children not to meet weight targets on growth curves. PEM impairs brain, immune system, and intestinal mucosal func tions (see Chapters 62 and 64). The DRI for protein is provided in Table 60.3. Numerous factors influence dietary requirements for protein, including gender, age, growth stage, pregnancy, lactation, the presence of illness, the nutri tional adequacy of an individuals diet, and genetics. The most impor tant determinant of protein requirements is energy intake because insufficient energy intake will lead to protein catabolism to maintain energy balance, effectively increasing protein intake requirements. The EAR and RDA take into account protein required for growth and maintenance, but the RDA accounts for variation in requirements for a particular population that may exist as a result of differences in mainte nance needs, protein accrual rates, and the efficiency of dietary protein accrual. Thus the RDA exceeds the EAR and most protein needs for individuals of a specific group. The average intake of protein from poultry, meat, eggs, nuts, seeds, and soy products differs by age and gender. According to the 2020 2025 DGA and based on National
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Health and Nutrition Examination Survey (NHANES) data from 2015 to 2016, the average daily intake of protein for males and females age 2 4 years and 5 8 years is within rec ommended ranges. In children age 9 13 years, average protein intake barely meets the lower end of recommended intake for both males and females. For adolescents 14 years of age and above, males have average daily protein intakes within the recommended range; that for females falls short of the minimum recommended daily intake. A UL for pro tein has not been set because of insufficient data; however, excessively high intakes can result in increased urinary calcium excretion that may increase the risk of renal calculi. Intake of protein or specific amino acids needs to be limited in some health conditions, such as renal dis ease, decompensated liver disease, and metabolic diseases such as phe nylketonuria and maple syrup urine disease, in which specific amino acids can be toxic. Conclusive evidence for harm in otherwise healthy individuals from high protein intakes is lacking. Protein intake neces sary to meet micronutrient needs, especially during the first 2 years of postnatal life, will typically exceed recommended protein intakes, thus requiring micronutrient supplementation to prevent insufficiency or deficiency. The amino acid content of dietary protein is also important. The standard by which a proteins quality is judged is its ability to support adequate growth. Certain amino acids are indispensableessential, and humans depend on dietary sources to meet adequacy and prevent defi ciency. Certain amino acids are termed conditionally indispensable, meaning they can be endogenously produced but require an exogenous source (i.e., diet) in certain disease conditions or during a certain life stage. An example would be the increased requirements for cysteine, tyrosine, and arginine in newborns because of enzyme immaturity (Table 60.4). DRI recommendations regarding protein intake assume adequate provision of indispensable amino acids and high digestibility. Human milk contains both the indispensable and conditionally indis pensable amino acids and therefore meets the protein requirements for infants. Breast milk is considered the optimal protein source for infants and is the reference amino acid composition by which biologic qual ity is determined for infants. If a single amino acid in a food protein source is low or absent but is required to support normal metabolism, that specific amino acid becomes the limiting nutrient in that food. Animal protein, unlike plant protein, contains sufficient indispensable Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 394 Part V u Nutrition amino acids and typically is more digestible (95) than plant source proteins (7080). To ensure appropriate growth and to promote satiety, children should consume the recommended amount of protein. Specific recom mendations for appropriate dietary protein sources to meet indispens able amino acid requirements are available for groups adopting specific diets, such as vegetarians and vegans. Including mixtures of protein
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sources (e.g., legumes and corn) and using a variety of food sources to provide all of the required amino acids are strategies advocated for vegetarians and vegans (see Chapter 61). CARBOHYDRATES Carbohydrates are abundant in many foods, including cereals, grains, fruits, and vegetables, and provide approximately 4 kcalg of energy. Dietary carbohydrates include monosaccharides, which contain one sugar molecule (e.g., glucose, fructose, galactose); disaccharides, which contain two sugar molecules (e.g., sucrose, lactose, maltose); oligosaccharides or polysaccharides, which contain multiple sugar molecules in a chain or complex configuration (e.g., starch, nonstarch polysaccharides like fiber); and sugar alcohols. Dietary carbohydrates are absorbed across the intestinal epithelium and converted to glucose in the liver. Glucose serves as the essential energy source for eryth rocytes and the central nervous system and is a major energy source for all other cells. The requirements for carbohydrates are based on the average minimum amount of glucose used by the brain. Chronic low carbohydrate intake (e.g., less than 10 of total caloric intake) results in ketosis. Although a UL for carbohydrates has not been set, a maximal intake of 10 of total energy intake from added sugars, such as syrups and other caloric sweeteners, has been proposed in the 20202025 DGA. Added sugars do not contribute essential nutrients and function to sweeten foods and beverages. Naturally occurring sugars, such as in milk (lactose) or fruits (fructose), are not included. Higher intakes of added sugar can displace other macronutrients and micronutri ents and increase the risk for nutrient deficiency and excessive energy intake. There is no benefit from consuming added sugars as discretion ary calorie intake. The excess calories from added sugars may displace more nutrient dense foods and make it difficult to meet nutrient needs while remaining within the recommended total caloric intake. The recommended AMDR for carbohydrates is based on data sug gesting a risk for coronary artery disease (CAD) with diets high in refined carbohydrates and low in fat (see Table 60.2). These diets, com pared with diets with higher fat intake, result in high triglyceride levels, low high density lipoprotein (HDL) cholesterol, and small LDL choles terol particles and are associated with an increased risk of CAD, espe cially in sedentary overweight individuals. Diets within the AMDR for carbohydrates and fats minimize the risks of diabetes, obesity, and CAD. Diets with less than the minimum AMDR for carbohydrate most likely do not meet the AI for fiber (see Table 60.3). Most carbohydrates are present as starches or sugars in food. Sim ple sugars (monosaccharides and disaccharides) are often added to foods and beverages during food preparation, processing, and packag ing to enhance their palatability and also act as preservatives. Sugar sweetened beverages, including nondiet soft drinks, juice drinks, iced tea, and sport drinks, are major contributors to added sugars in the diet of U.S. children and adolescents (Fig. 60.4). Added sugars are associ ated with increased risk for obesity, diabetes, and dental caries. Fruc tose is one such added sugar in the form of high
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fructose corn syrup, which is ubiquitous in the U.S. diet. Added fructose increases HDL and triglyceride production in the liver and serum uric acid, which increases systolic blood pressure and is associated with nonalcoholic fatty liver disease and metabolic syndrome. Excessive fructose intake, such as in the form of fruit juices, may be associated with diarrhea, abdominal pain, and failure to thrive in children. Fructose consumed in whole fruits rarely contributes to these side effects because its sys temic absorption and metabolic effects are mitigated by the fact that it is complexed with fiber. The glycemic index is a measure of peak blood glucose concentra tion 2 hours after ingestion of a given food compared with a reference standard (slice of white bread). The glycemic index has predictable effects on blood glucose, hemoglobin A1C, insulin, triglycerides, and HDL cholesterol. Lower glycemic index foods are recommended and may reduce the risk of insulin resistance and CV disease. Examples of low glycemic index foods include oat bran, muesli, barley, carrots, nonstarchy vegetables, and most fruits. FIBER Fiber consists of nondigestible carbohydrates (i.e., nonstarch polysac charides and nonpolysaccharides such as lignins), mostly derived from plant sources, such as whole grains, fruits, and vegetables, that escape digestion and reach the colon almost 100 intact. Fiber can be classi fied as fermentable and nonfermentable. Fermentable fibers are found in beans, fruits, and products containing oats or psyllium, and non fermentable fiber is found in whole grains and vegetables. The DRI classification considers total fiber intake to be composed of dietary fiber (nondigestible carbohydrates and lignins intrinsic to plants that are fermented by colonic bacteria) and functional fiber (nondigestible carbohydrates isolated from plants or manufactured for use as dietary supplements). Although functional fibers may improve constipation and glucose absorption, they do not contain the other beneficial phy tochemicals and nutrients of naturally occurring fiber found in whole foods. Functional fibers have been added to cereals, salad dressings, soups, baked goods, and meal replacements with the aim of increasing fiber intake. Dietary fiber may help reduce intestinal cell dysplasia by diluting toxins, carcinogens, and tumor promoters; decreasing transit time, thereby reducing colonic mucosal exposure; and promoting toxin expulsion in the fecal stream. Dietary fiber that is resistant to colonic Table 60.4 Indispensable, Dispensable, and Conditionally Indispensable Amino Acids in the Human Diet INDISPENSABLE DISPENSABLE CONDITIONALLY INDISPENSABLE PRECURSORS OF CONDITIONALLY INDISPENSABLE Histidine Isoleucine Leucine Lysine Methionine Phenylalanine Threonine Tryptophan Valine Alanine Aspartic acid Asparagine Glutamic acid Serine Arginine Cysteine Glutamine Glycine Proline Tyrosine Glutamineglutamate, aspartate Methionine, serine Glutamic acidammonia Serine, choline Glutamate Phenylalanine Conditionally indispensable is defined as requiring a dietary source when endogenous synthesis cannot meet metabolic need. Although histidine is considered indispensable, unlike the other 8 indispensable amino acids, it does not fulfill the criteria of reducing protein deposition and inducing negative nitrogen balance promptly on removal from the diet. Adapted from Otten JJ, Hellwig JP, Meyers LD (eds). Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: Institute of Medicine, National Academies Press;
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2006. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 60 u Nutritional Requirements 395 degradation may also play a role in maintaining and promoting stool bulk and in regulating intraluminal pressure and colonic wall resis tance, disordered colonic motility, or both. Lack of certain types of dietary fiber is associated with constipation and diverticulosis. All types of dietary fiber slow gastric emptying and promote satiety, and thus may help to regulate appetite. Dietary fiber may decrease the rate of release and absorption of simple sugars and may help regulate blood sugar concentration by lowering postprandial blood glucose lev els. Dietary fiber has a low glycemic index and may have a beneficial effect on insulin sensitivity. Fiber also binds luminal cholesterol and reduces absorption and enterohepatic circulation of the cholesterol in bile salts (e.g., with the intake of more viscous forms of dietary fiber, such as pectin). Guar gum, oat products, and pectin (i.e., fermentable viscous fiber) lower serum cholesterol, whereas nonfermentablenon viscous fiber (e.g., flax, wheat bran) may reduce serum triglycerides. Fiber such as psyllium, resistant dextrins, and resistant starch may lower both serum LDL cholesterol and triglycerides. Low fiber intake in Western society has been associated with the increasing incidence and prevalence of diabetes, obesity, CV disease, colon cancer, and IBD. There is a dynamic interplay between the colonic bacterial milieu and the diet. The metabolic fate of fiber is influenced primarily by colonic bacteria, which render it susceptible to fermentation, depending on the structure of the fiber (e.g., pectin, oat bran). Common byproducts of colonic fermentation include carbon dioxide, methane (in addition to other gases), oligofructose (also known as a prebiotic, a substrate that nourishes beneficial commensal GI microbiota), and short chain fatty acids (SCFAs). The common SCFAs produced by fermentation include acetate, butyrate, and propionate. SCFAs influence colonic physiology by stimulating colonic blood flow and fluid and electrolyte uptake. Butyrate is the preferred fuel for the colonocyte and may have a role in maintaining the normal phenotype in these cells. Good sources of fiber include beans, peas, leafy and cruciferous vegetables, fruits, and whole grains. The observed benefits of diets rich in fruits and vegetables may be mediated by the fiber they contain and also by the other compounds and micronutrients (e.g., polyphenols, carotenoids) they contain. Data are insufficient to establish an EAR for dietary fiber. AI for dietary fiber has been established based on the intake levels associ ated with reducing risk for CV disease and in lowering or normalizing serum cholesterol (see Table 60.3). Several recommendations address dietary fiber intake in children based on body weight or as a propor tion of daily calories consumed. The IOM recommends an AI for fiber of 14 g per 1,000 kcal of energy consumed (see Table 60.3), which for younger children may be unrealistic to achieve. The equation for the range
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of recommended daily fiber intake in grams Age (years) 5 to 10 grams per day. The recommendations do not specify type of fiber and predate the newer definitions of fiber. A UL has not been established for fiber, which is not thought to be harmful to human health. Some types of fiber, such as fermentable oli gosaccharides, may exert symptoms on the basis of their digestibility, by product formation, and interactions with GI microbiota. Excessive intake of fermentable oligosaccharides (e.g., fructooligosaccharides such as onions), disaccharides (e.g., lactose), monosaccharides (e.g., fructose), and polyols (e.g., sorbitol) (aka FODMAPs) is associated with increased risk for GI symptoms along the functional abdominal pain, functional GI disorders (IBS), and IBD. Restricted intake or substitution with lower FODMAP foods may be beneficial. Substi tutions within the same food groups can shift from a high FODMAP diet to a low FODMAP diet, which may provide GI symptom relief. For example, substituting cucumber for celery would be exchanging a high FODMAP food for a low FODMAP food. Dietary management for some conditions may put certain children at risk of low fiber intake. Gluten free diets used for celiac disease are often low in fiber. In such cases, gluten free sources of fiber should be recommended, such as tapioca, flax, corn, rice, sorghum, and quinoa. Fig. 60.4 Top sources and average intakes of added sugars: U.S. population age 1 year and older. Estimates based on 2 day dietary intake data, weighted, from What We Eat in America (WWEIA), NHANES, 2013 2016. (From the Dietary Guidelines for Americans, 2020 2025, Chapter 1: Nutrition and Health Across the Lifespan. Fig. 1.10. https:www.dietaryguidelines.govsitesdefaultfiles2020 12DietaryGuidelinesforAmericans2020 2025.pdf.) Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 396 Part V u Nutrition MICRONUTRIENTS See Chapters 66 72. Vitamins and minerals, the dietary micronutrients, are essential for growth and development and contribute to a host of physiologic func tions. Many U.S. children may have suboptimal intake of iron, zinc, potassium, calcium, and vitamins D, E, and K, and excess intake of sodium. Dietary recommendations for micronutrients were originally established to prevent deficiency and currently also include the impact of micronutrients on long term health outcomes (Table 60.5). Food fortification is an effective strategy to prevent some nutrient deficien cies and has been successfully implemented to prevent iodine, folate, and vitamin D deficiencies. The DRI for 0 6 months for all micronutrients are AIs, because data are considered to be insufficient to establish an EAR on which an RDA would be based. The AI for the first 6 months of postnatal life is based on the daily mean nutrient intake supplied by human milk for healthy, full term infants who are exclusively breastfed. For approximately the first 6 months of postnatal life for healthy term infants, an adequately nourished mother produces human milk with adequate amounts of the majority of micronutrients; exceptions
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are iron and zinc, concen trations of which are unrelated to maternal intake. In the early post natal months, infants rely on body stores and iron available from the relatively high erythron (especially with delayed cord clamping), and thus the actual dietary requirement for iron is very modest. Infants born prematurely andor with evidence of fetal growth restriction are likely to have low iron stores at birth and thus may need exogenous iron earlier than 6 months. Zinc concentrations in human milk decline sharply over the first 3 4 months of lactation and are insufficient to meet needs by approximately 6 months. Thus after about 6 months, sources of both iron and zinc are required from complementary foods, such as pureed meats, fortified foods (e.g., infant cereals), or from supplements. Iron Iron requirements are relatively higher during infancy and early child hood than later in life and are higher for menstruating females than for males of similar age groups (see Chapter 72). Iron from animal protein is more bioavailable than that found in animal source foods such as milk or plant sources because it is already incorporated into heme moi eties in blood and muscle. Iron deficiency is the most common micro nutrient deficiency in the world and is associated with iron deficiency anemia and neurocognitive deficits in some children. Zinc Zinc deficiency is estimated to affect millions of children in low resource settings and is associated with increased risk for impaired lin ear growth (stunting), impaired immune function, and increased risk for respiratory and diarrheal diseases. In high resource settings, mild deficiency may occur in older infants and toddlers if dietary choices do not include meat or fortified products. Whole grains, legumes, and other high protein plant sources contain good amounts of zinc, but the absorption bioavailability will be lower compared to animal source foods. Vitamin D Vitamin D insufficiency is more common than previously thought in infants and children. Vitamin D is central to calcium and bone metabolism but is also an important determinant of various nonos seous health outcomes (see Chapter 69). Children of all ages with darker skin and those who do not consume fortified dairy products should be considered for screening for vitamin D deficiency. The DRI for vitamin D is based on its effects on calcium status and bone health. The goal is to achieve serum 25 hydroxyvitamin D levels 50 nmolL (30 ngdL). Breast milk is a poor source of vitamin D. The American Academy of Pediatrics (AAP) recommends total vitamin D intake of 400 IUday for infants (0 to 12 months). A supplement is recommended for all breastfed infants to ensure sufficient intake. The RDA of vitamin D is currently 600 units daily for healthy children 1 18 years of age. Calcium Calcium is key to bone health. Adequacy is determined in part by bone mineral content and bone mineral density (BMD). The main stor age organs for calcium are the bones and teeth. Bone mineral accre tion occurs primarily during childhood,
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with peak bone mass being achieved by the second to third decade of life. Calcium recommen dations include a change from an AI to RDA, in terms of strength of evidence for recommendations, and increased UL in 9 to 18 year olds (Table 60.6). There are no adequate biomarkers to assess calcium status in healthy children because serum calcium is tightly regulated (regard less of intake and total body calcium) by changes in parathyroid hor mone and calcitriol levels. Maintaining adequate serum calcium level despite inadequate intake could come at the expense of BMD. Therefore in the long term, reduced BMD could serve as a surrogate marker of chronic calcium intake and status. It is important to note other deter minants of BMD are age, gender, genetic ethnic factors, hormonal sta tus, physical activity, and weight. Assessments of calcium status should include calcium intake in the diet. It is also important to educate fami lies on additional and alternative sources of calcium (including calcium supplementation) if calcium intake is determined to be low. Electrolytes Potassium (K) and sodium (Na) are the main intracellular and extra cellular cations, respectively, and are involved in transport of fluids and nutrients across the cellular membrane. The AI for potassium is related to its effects in maintaining a healthy blood pressure, reducing risk for nephrolithiasis, and supporting bone health. Moderate potassium defi ciency occurs even in the absence of hypokalemia and can result in increased blood pressure, stroke, and other CV disease. For people at increased risk of hypertension and who are salt sen sitive, reducing sodium intake and increasing potassium intake is advised. Leafy green vegetables, vine fruits (e.g., tomatoes, eggplant, zucchini, pumpkin), and root vegetables (e.g., yams, beets) are good sources of potassium (see Table 60.6). People with impaired renal func tion may need to reduce potassium intake, because hyperkalemia can increase the risk for fatal cardiac arrhythmias among these patients. Most dietary sodium (i.e., sodium chloride, or table salt) in the United States is found in processed foods, breads, and condiments (Fig. 60.5). Sodium salt (NaCl) is added to foods to serve as a preservative and enhance palatability. Sodium has an AI, but given the risk of table saltrelated hypertension, an UL has also been set. The UL threshold may be even lower in certain populations, who on average may be more sodium salt sensitive, and for those with hypertension or preexisting renal disease. Dietary sodium intake also displaces potassium intake. Elevated sodium:potassium ratios can increase the risk for nephrolithi asis. Intakes of 2,300 mg sodium (approximately 1 tsp of table salt) per day are recommended. The average daily salt intake for most people in the United States and Canada exceeds both the AI and UL. For popula tions with or at risk of hypertension and renal disease, sodium intake should be decreased to 1,500 mgday and potassium intake increased to 4,700 mgday. For persons with hypertension, additional dietary guidelines are available from the Dietary Approaches to Stop Hyper tension (DASH) eating
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plan. WATER The daily water requirement and water content as a proportion of body weight are highest in infants and decrease with age. Water intake is achieved with liquid and food intake, and losses include excretion in the urine and stool, as well as insensible and evaporative losses through the skin and respiratory tract. An AI has been established for water (see Table 60.6). Special considerations are required by life stages and by BMR, physical activity, body proportions (surface area to volume), environment, and underlying medical conditions. Breast milk and infant formula provide adequate water, and additional water or other fluid intake is not required until complementary foods are introduced. Water contains no calories, but the concern is that additional water intake in young infants will decrease breast milk intake and displace the intake of essential nutrients during this phase of rapid rate of growth and high metabolic activity. The relatively higher fluid needs of Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. C hap ter 6 0 u N utritio nal R eq uirem ents 3 9 7 Table 60.5 Dietary Reference Intakes for Vitamins NUTRIENT FUNCTION LIFE STAGE GROUP RDA OR AI UL SELECTED FOOD SOURCES ADVERSE EFFECTS OF EXCESSIVE CONSUMPTION SPECIAL CONSIDERATIONS Biotin (vitamin B7) Coenzyme in synthesis of fat, glycogen, and amino acids Infants (gday) Liver, smaller amounts in fruits and meats Limited data to support adverse effects with excess; however, high intakes still should be taken with precaution. None 0 6 mo 5 ND 7 12 mo 6 ND Children (gday) 1 3 yr 8 ND 4 8 yr 12 ND Males (gday) 9 13 yr 20 ND 14 18 yr 25 ND 19 21 yr 30 ND Females (gday) 9 13 yr 20 ND 14 18 yr 25 ND 19 21 yr 30 ND Pregnancy (gday) 18 yr 30 ND 19 21 yr 30 ND Lactation (gday) 18 yr 35 ND 19 21 yr 35 ND Choline Precursor for acetylcholine, phospholipids, and betaine Infants (mgday) Milk, liver, eggs, peanuts Fishy body odor, sweating, salivation, hypotension, hepatotoxicity Patients with trimethylaminuria, renal disease, liver disease, depression, and Parkinson disease may be at risk for adverse effects with intakes at the UL. AIs have been set for choline, but there are little data to assess whether a dietary supply of choline is needed at all stages of the life cycle because the choline requirement might be met by endogenous synthesis at some of these stages. 0 6 mo 125 ND 7 12 mo 150 ND Children (mgday) 1 3 yr 200 1,000 4 8 yr 250 1,000 Males (mgday) 9 13 yr 375 2,000 14 18 yr 550 3,000 19 21 yr 550 3,500 Females (mgday) 9 13 yr 375 2,000 14 18 yr 400 3,000 19 21 yr 425 3,500 Pregnancy (mgday) 18 yr 450 3,000 19 21 yr 450
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3,500 Lactation (mgday) 18 yr 550 3,000 19 21 yr 550 3,500 Continued D ow nloaded for m oham ed ahm ed (dr.m m s2020 gm ail.com ) at U niversity of Southern C alifornia from C linicalK ey.com by Elsevier on A pril 20, 2024. For personal use only. N o other uses w ithout perm ission. C opyright 2024. Elsevier Inc. A ll rights reserved. 3 9 8 P art V u N utrition Table 60.5 Dietary Reference Intakes for Vitaminscontd NUTRIENT FUNCTION LIFE STAGE GROUP RDA OR AI UL SELECTED FOOD SOURCES ADVERSE EFFECTS OF EXCESSIVE CONSUMPTION SPECIAL CONSIDERATIONS Folate (folic acid, vitamin B9, folacin); pteroyl polyglutamates given as dietary folate equivalents (DFEs) 1 DFE 1 g food folate 0.6 g folate from fortified food, or as supplement consumed with food 0.5 g of supplement taken on empty stomach Coenzyme in metabolism of nucleic and amino acids Prevents megaloblastic anemia Infants (gday) Enriched cereal, grains, dark leafy vegetables, enriched and whole grain breads and bread products, fortified ready to eat cereals Masks neurologic complications in people with vitamin B12 deficiency. No adverse effects with folate from food or supplements have been reported; however, high intakes still should be taken with precaution. UL applies to synthetic forms obtained from supplements and or fortified foods. Poor intake associated with neural tube defects; therefore all women who can become pregnant should consume, in addition to intake of food folate from a varied diet, 400 gday from supplements or fortified foods. 0 6 mo 65 ND 7 12 mo 80 ND Children (gday) 1 3 yr 150 300 4 8 yr 200 400 Males (gday) 9 13 yr 300 600 14 18 yr 400 800 19 21 yr 400 1,000 Females (gday) 9 13 yr 300 600 14 18 yr 400 800 19 21 yr 400 1,000 Pregnancy (gday) 18 yr 600 800 19 21 yr 600 1,000 Lactation (gday) 18 yr 500 800 19 21 yr 500 1,000 Niacin (vitamin B3) Includes nicotinic acid amide, nicotinic acid (pyridine 3 carboxylic acid), and derivatives that exhibit biologic activity of nicotinamide Given as niacin equivalents (NE) 1 mg niacin 60 mg tryptophan Age 0 6 mo: preformed niacin (not NE). Coenzyme or cosubstrate in many biologic reduction and oxidation reactions, thus required for energy metabolism Infants (mgday) Meat, fish, poultry, enriched and whole grain breads and bread products, fortified ready to eat cereals No evidence of adverse effects from consuming naturally occurring niacin in food. Adverse effects from niacin containing supplements can include flushing and GI distress. UL for niacin applies to synthetic forms obtained from supplements, fortified food, or a combination of these. Extra niacin may be required by persons treated with hemodialysis or peritoneal dialysis or those with malabsorption syndrome. 0 6 mo 2 ND 7 12 mo 4 ND Children (mgday) 1 3 yr 6 10 4 8 yr 8 15 Males (mgday) 9 13 yr 12 20 14 18 yr 16 30 19 21 yr 16 35 Females
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(mgday) 9 13 yr 12 20 14 18 yr 14 30 19 21 yr 14 35 Pregnancy (mgday) 18 yr 18 30 19 21 yr 18 35 Lactation (mgday) 18 yr 17 30 19 21 yr 17 35 D ow nloaded for m oham ed ahm ed (dr.m m s2020 gm ail.com ) at U niversity of Southern C alifornia from C linicalK ey.com by Elsevier on A pril 20, 2024. For personal use only. N o other uses w ithout perm ission. C opyright 2024. Elsevier Inc. A ll rights reserved. C hap ter 6 0 u N utritio nal R eq uirem ents 3 9 9 Table 60.5 Dietary Reference Intakes for Vitaminscontd NUTRIENT FUNCTION LIFE STAGE GROUP RDA OR AI UL SELECTED FOOD SOURCES ADVERSE EFFECTS OF EXCESSIVE CONSUMPTION SPECIAL CONSIDERATIONS Pantothenic acid (vitamin B5) Coenzyme in fatty acid metabolism Infants (mgday) Chicken, beef, potatoes, oats, cereals, tomato products, liver, kidney, yeast, egg yolk, broccoli, whole grains Doses greater than 10 mgday may cause mild diarrhea or mild intestinal distress; therefore high intakes should be taken with precaution. Doses are age dependent and if the patient is pregnant or lactating.0 6 mo 1.7 ND 7 12 mo 1.8 ND Children (mgday) 1 3 yr 2 ND 4 8 yr 3 ND Males (mgday) 9 13 yr 4 ND 14 18 yr 5 ND 19 21 yr 5 ND Females (mgday) 9 13 yr 4 ND 14 18 yr 5 ND 19 21 yr 5 ND Pregnancy (mgday) 18 yr 6 ND 19 21 yr 6 ND Lactation (mgday) 18 yr 7 ND 19 21 yr 7 ND Riboflavin (vitamin B2) Coenzyme in numerous redox reactions Infants (mgday) Organ meats, milk, bread products, fortified cereals No adverse effects associated with vitamin B2 consumption from food or supplements have been reported; however, high intakes still should be taken with precaution. None 0 6 mo 0.3 ND 7 12 mo 0.4 ND Children (mgday) 1 3 yr 0.5 ND 4 8 yr 0.6 ND Males (mgday) 9 13 yr 0.9 ND 14 18 yr 1.3 ND 19 21 yr 1.3 ND Females (mgday) 9 13 yr 0.9 ND 14 18 yr 1.0 ND 19 21 yr 1.1 ND Pregnancy (mgday) 18 yr 1.4 ND 19 21 yr 1.4 ND Lactation (mgday) 18 yr 1.6 ND 19 21 yr 1.6 ND Continued D ow nloaded for m oham ed ahm ed (dr.m m s2020 gm ail.com ) at U niversity of Southern C alifornia from C linicalK ey.com by Elsevier on A pril 20, 2024. For personal use only. N o other uses w ithout perm ission. C opyright 2024. Elsevier Inc. A ll rights reserved. 4 0 0 P art V u N utrition Table 60.5 Dietary Reference Intakes for Vitaminscontd NUTRIENT FUNCTION LIFE STAGE GROUP RDA OR AI UL SELECTED FOOD SOURCES ADVERSE EFFECTS OF EXCESSIVE CONSUMPTION SPECIAL CONSIDERATIONS Thiamin (vitamin B1,) Coenzyme in metabolism of carbohydrates and branched chain amino acids Infants (mgday) Enriched, fortified, or whole grain
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products, bread and bread products, mixed foods whose main ingredient is grain, ready to eat cereals No adverse effects associated with vitamin B1 consumption from food or supplements have been reported; however, high intakes still should be taken with precaution. Persons being treated with hemodialysis or have a malabsorption syndrome may have increased needs for vitamin B1. 0 6 mo 0.2 ND 7 12 mo 0.3 ND Children (mgday) 1 3 yr 0.5 ND 4 8 yr 0.6 ND Males (mgday) 9 13 yr 0.9 ND 14 18 yr 1.2 ND 19 21 yr 1.2 ND Females (mgday) 9 13 yr 0.9 ND 14 18 yr 1.0 ND 19 21 yr 1.1 ND Pregnancy (mgday) 18 yr 1.4 ND 19 21 yr 1.4 ND Lactation (mgday) 18 yr 1.4 ND 19 21 yr 1.4 ND Vitamin A Includes provitamin A carotenoids that are dietary precursors of retinol Given as retinol activity equivalents (RAEs) 1 RAE 1 g retinol, 12 g carotene, 24 g carotene, or 24 g cryptoxanthin To calculate RAEs from REs of provitamin A carotenoids in food, divide REs by 2 For preformed vitamin A in food or supplements and for provitamin A carotenoids in supplements, 1 RE 1 RAE Required for normal vision, gene expression, reproduction, embryonic development, and immune function Infants (gday) Liver, dairy products, fish, dark colored fruit, leafy vegetables Teratologic effects, liver toxicity (from preformed vitamin A only). Persons with high alcohol intake, preexisting liver disease, hyperlipidemia, or severe protein malnutrition may be susceptible to the adverse effects of excess preformed vitamin A intake. Carotene supplements are advised only to serve as a provitamin A source for persons at risk for vitamin A deficiency. 0 6 mo 400 600 7 12 mo 500 600 Children (gday) 1 3 yr 300 600 4 8 yr 400 900 Males (gday) 9 13 yr 600 1,700 14 18 yr 900 2,800 19 21 yr 900 3,000 Females (gday) 9 13 yr 600 1,700 14 18 yr 700 2,800 19 21 yr 700 3,000 Pregnancy (gday) 18 yr 750 2,800 19 21 yr 770 3,000 Lactation (gday) 18 yr 1,200 2,800 19 21 yr 1,300 3,000 D ow nloaded for m oham ed ahm ed (dr.m m s2020 gm ail.com ) at U niversity of Southern C alifornia from C linicalK ey.com by Elsevier on A pril 20, 2024. For personal use only. N o other uses w ithout perm ission. C opyright 2024. Elsevier Inc. A ll rights reserved. C hap ter 6 0 u N utritio nal R eq uirem ents 4 0 1 Table 60.5 Dietary Reference Intakes for Vitaminscontd NUTRIENT FUNCTION LIFE STAGE GROUP RDA OR AI UL SELECTED FOOD SOURCES ADVERSE EFFECTS OF EXCESSIVE CONSUMPTION SPECIAL CONSIDERATIONS Pyridoxine (vitamin B6) Comprises a group of six related compounds: pyridoxal, pyridoxine, pyridoxamine, and 5 phosphates (PLP, PNP, PMP) Coenzyme in metabolism of amino acids, glycogen, and sphingoid bases Infants (mgday) Fortified cereals, organ meats, fortified soy based meat substitutes No adverse effects associated with vitamin
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B6 from food have been reported; however, high intakes still should be taken with precaution. Sensory neuropathy, ataxia, and nausea have occurred from high intakes (1,000 mgday) of supplemental forms. Deficiencies often occur when other B vitamins in the body are low, particularly vitamin B12 and folic acid. Risk of developing deficiency is associated with conditions such as kidney disease, celiac disease, inflammatory bowel disease, rheumatoid arthritis, and alcohol use. 0 6 mo 0.1 ND 7 12 mo 0.3 ND Children (mgday) 1 3 yr 0.5 30 4 8 yr 0.6 40 Males (mgday) 9 13 yr 1.0 60 14 18 yr 1.3 80 19 21 yr 1.3 100 Females (mgday) 9 13 yr 1.0 60 14 18 yr 1.2 80 19 21 yr 1.3 100 Pregnancy (mgday) 18 yr 1.9 80 19 21 yr 1.9 100 Lactation (mgday) 18 yr 2.0 80 19 21 yr 2.0 100 Cobalamin (vitamin B12) Coenzyme in nucleic acid metabolism Prevents megaloblastic anemia Infants (gday) Fortified cereals, meat, fish, poultry Because 1030 of older people malabsorb food bound vitamin B12, those 50 yr are advised to meet their RDA mainly by consuming foods fortified with vitamin B12 or a supplement containing vitamin B12. 0 6 mo 0.4 ND 7 12 mo 0.5 ND Children (gday) 1 3 yr 0.9 ND 4 8 yr 1.2 ND Males (gday) 9 13 yr 1.8 ND 14 18 yr 2.4 ND 19 21 yr 2.4 ND Females (gday) 9 13 yr 1.8 ND 14 18 yr 2.4 ND 19 21 yr 2.4 ND Pregnancy (gday) 18 yr 2.6 ND 19 21 yr 2.6 ND Lactation (gday) 18 yr 2.8 ND 19 21 yr 2.8 ND Continued D ow nloaded for m oham ed ahm ed (dr.m m s2020 gm ail.com ) at U niversity of Southern C alifornia from C linicalK ey.com by Elsevier on A pril 20, 2024. For personal use only. N o other uses w ithout perm ission. C opyright 2024. Elsevier Inc. A ll rights reserved. 4 0 2 P art V u N utrition Table 60.5 Dietary Reference Intakes for Vitaminscontd NUTRIENT FUNCTION LIFE STAGE GROUP RDA OR AI UL SELECTED FOOD SOURCES ADVERSE EFFECTS OF EXCESSIVE CONSUMPTION SPECIAL CONSIDERATIONS Vitamin C (ascorbic acid, dehydroascorbic acid) Cofactor for reactions requiring reduced copper or iron metalloenzyme and as a protective antioxidant Infants (mgday) Citrus fruit, tomatoes, tomato juice, potatoes, brussels sprouts, cauliflower, broccoli, strawberries, cabbage, spinach GI disturbances, kidney stones, excess iron absorption Smokers require additional 35 mgday of vitamin C over that needed by nonsmokers. Nonsmokers regularly exposed to tobacco smoke should ensure they meet the RDA for vitamin C. 0 6 mo 40 ND 7 12 mo 50 ND Children (mgday) 1 3 yr 15 400 4 8 yr 25 650 Males (mgday) 9 13 yr 45 1,200 14 18 yr 75 1,800 19 21 yr 90 2,000 Females (mgday) 9 13 yr 45 1,200 14 18 yr 65 1,800 19 21 yr 75 2,000 Pregnancy (mgday) 18 yr 80 1,800 19
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21 yr 85 2,000 Lactation (mgday) 18 yr 115 1,800 19 21 yr 120 2,000 Vitamin E ( tocopherol) tocopherol includes RRR tocopherol, the only form of tocopherol that occurs naturally in foods, and the 2R stereoisomeric forms of tocopherol (RRR , RSR , RRS , and RSS tocopherol) that occur in fortified foods and supplements It does not include the 2S stereoisomeric forms of tocopherol (SRR , SSR , SRS , and SSS tocopherol), also found in fortified foods and supplements A metabolic function has not yet been identified. Vitamin Es major function appears to be as a nonspecific chain breaking antioxidant. Infants (mgday) Vegetable oil, unprocessed cereal grains, nuts, fruit, vegetables, meat No evidence of adverse effects from consuming vitamin E naturally occurring in food. Adverse effects from supplements may include hemorrhagic toxicity. UL applies to any form of tocopherol obtained from supplements, fortified foods, or a combination of these. Persons receiving anticoagulant therapy are at risk of excess bleeding when taking vitamin E supplements in doses greater than 1,000 mg day. 0 6 mo 4 ND 7 12 mo 5 ND Children (mgday) 1 3 yr 6 200 4 8 yr 7 300 Males (mgday) 9 13 yr 11 600 14 18 yr 15 800 19 21 yr 15 1,000 Females (mgday) 9 13 yr 11 600 14 18 yr 15 800 19 21 yr 15 1,000 Pregnancy (mgday) 18 yr 15 800 19 21 yr 15 1,000 Lactation (mgday) 18 yr 19 800 19 21 yr 19 1,000 D ow nloaded for m oham ed ahm ed (dr.m m s2020 gm ail.com ) at U niversity of Southern C alifornia from C linicalK ey.com by Elsevier on A pril 20, 2024. For personal use only. N o other uses w ithout perm ission. C opyright 2024. Elsevier Inc. A ll rights reserved. C hap ter 6 0 u N utritio nal R eq uirem ents 4 0 3 Table 60.5 Dietary Reference Intakes for Vitaminscontd NUTRIENT FUNCTION LIFE STAGE GROUP RDA OR AI UL SELECTED FOOD SOURCES ADVERSE EFFECTS OF EXCESSIVE CONSUMPTION SPECIAL CONSIDERATIONS Vitamin K Coenzyme during synthesis of many proteins involved in blood clotting and bone metabolism Infants (gday) Green vegetables (collards, spinach, salad greens, broccoli), brussels sprouts, cabbage, plant oil, margarine No adverse effects associated with vitamin K consumption from food or supplements have been reported in humans or animals; however, high intakes still should be taken with precaution. Patients receiving anticoagulant therapy or taking long term antibiotics should monitor vitamin K intake.0 6 mo 2.0 ND 7 12 mo 2.5 ND Children (gday) 1 3 yr 30 ND 4 8 yr 55 ND Males (gday) 9 13 yr 60 ND 14 18 yr 75 ND 19 21 yr 120 ND Females (gday) 9 13 yr 60 ND 14 18 yr 75 ND 19 21 yr 90 ND Pregnancy (gday) 18 yr 75 ND 19 21 yr 90 ND Lactation (gday) 18 yr 75 ND 19 21 yr 90 ND Note: Starred ()
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numbers are adequate intake (AI) and bold numbers are RDA. RDAs and AIs may both be used as goals for individual intake. RDAs are set to meet the needs of 9798 of members in a group. For healthy breastfed infants, the AI is the mean intake. The AI for other life stage and gender groups is believed to cover the needs of all members of the group, but lack of data prevents specifying with confidence the percentage covered by this intake. UL is the maximum level of daily nutrient intake that is likely to pose no risk of adverse effects. Unless otherwise specified, the UL represents total intake from food, water, and supplements. Because of a lack of suitable data, ULs could not be established for potassium, water, or inorganic sulfate. In the absence of ULs, extra caution may be warranted in consuming levels above recommended intakes. ND amounts are not determinable because of a lack of data on adverse effects in this age group and concern with regard to lack of ability to handle excess amounts. Source of intake should be from food only to prevent high levels of intake. RDA for vitamin D in IUday: 400 if 1 yr age, 600 if 1 yr, lactating, or pregnant. AI, Adequate intake; GI, gastrointestinal; ND, not determinable; PLP, pyridoxal phosphate; PMP, pyridoxamine phosphate; PNP, pyridoxine phosphate; RDA, recommended dietary allowance; UL, upper limit of normal. Data from Dietary reference intakes for calcium, phosphorus, magnesium, vitamin D, and fluoride, 1997; Dietary reference intakes for thiamin, riboflavin, niacin, vitamin B6, folate, vitamin B12, pantothenic acid, biotin, and choline, 1998; Dietary reference intakes for vitamin C, vitamin E, selenium, and carotenoids, 2000; Dietary reference intakes for vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium, and zinc, 2001; Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids, 20022005; Dietary reference intakes for calcium and vitamin D, 2011. These reports may be accessed via www.nap.edu D ow nloaded for m oham ed ahm ed (dr.m m s2020 gm ail.com ) at U niversity of Southern C alifornia from C linicalK ey.com by Elsevier on A pril 20, 2024. For personal use only. N o other uses w ithout perm ission. C opyright 2024. Elsevier Inc. A ll rights reserved. 4 0 4 P art V u N utrition Table 60.6 Dietary Reference Intakes for Select Micronutrients and Water NUTRIENT FUNCTION LIFE STAGE GROUP AI (mgday) UL (mgday) SELECTED FOOD SOURCES ADVERSE EFFECTS OF EXCESSIVE CONSUMPTION SPECIAL CONSIDERATIONS Sodium Maintains fluid volume outside of cells and thus normal cell function Infants Processed foods with added sodium chloride (salt), benzoate, phosphate; salted meats, bread, nuts, cold cuts; margarine; butter; salt added to foods in cooking or at the table. Salt is about 40 sodium by weight. Hypertension, increased risk of cardiovascular disease and stroke AI is set based on ability to obtain a nutritionally adequate diet for other nutrients and to meet the needs
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for sweat losses for persons engaged in recommended levels of physical activity. Persons engaged in activity at higher levels or in humid climates resulting in excessive sweating might need more than the AI. UL applies to apparently healthy persons without hypertension; it thus may be too high for persons who already have hypertension. 0 6 mo 120 ND 7 12 mo 370 ND Children 1 3 yr 1,000 1,500 4 8 yr 1,200 1,900 Males 9 13 yr 1,500 2,200 14 21 yr 1,500 2,300 Females 9 13 yr 1,500 2,200 13 21 yr 1,500 2,300 Pregnancy and Lactation 14 yr 1,500 2,300 Chloride With sodium, maintains fluid volume outside of cells and thus normal cell function Infants Processed foods with added table salt, benzoate, phosphate; salted meats, nuts, cold cuts; margarine; butter; salt added to foods in cooking or at the table. Salt is about 60 chloride by weight. In concert with sodium, results in hypertension Chloride is lost, usually with sodium, in sweat and in vomiting and diarrhea. AI and UL are equimolar in amount to sodium because most of sodium in diet comes as table salt. 0 6 mo 180 ND 7 12 mo 570 ND Children 1 3 yr 1,500 2,300 4 8 yr 1,900 2,900 Males 9 13 yr 2,300 3,400 14 21 yr 2,300 3,600 Females 9 13 yr 2,300 3,400 13 21 yr 2,300 3,600 Pregnancy and Lactation 14 yr 2,300 3,600 Potassium Maintains fluid volume insideoutside of cells and thus normal cell function; acts to blunt the rise of blood pressure in response to excess sodium intake and decrease markers of bone turnover and recurrence of kidney stones Infants Fruits and vegetables, dried peas, dairy products, meats, nuts None documented from food alone, but potassium from supplements or salt substitutes can result in hyperkalemia and possibly sudden death if excess is consumed by persons with chronic renal insufficiency (kidney disease) or diabetes Persons taking drugs for cardiovascular disease such as ACE inhibitors, ARBs, or potassium sparing diuretics should be careful not to consume supplements containing potassium and might need to consume less than the AI. 0 6 mo 400 None set 7 12 mo 700 Children 1 3 yr 3,000 No UL 4 8 yr 3,800 Males 9 13 yr 4,500 14 21 yr 4,700 Females 9 13 yr 4,500 13 21 yr 4,700 Pregnancy 14 yr 4,700 Lactation 14 yr 5,100 D ow nloaded for m oham ed ahm ed (dr.m m s2020 gm ail.com ) at U niversity of Southern C alifornia from C linicalK ey.com by Elsevier on A pril 20, 2024. For personal use only. N o other uses w ithout perm ission. C opyright 2024. Elsevier Inc. A ll rights reserved. C hap ter 6 0 u N utritio nal R eq uirem ents 4 0 5 Table 60.6 Dietary Reference Intakes for Select Micronutrients and Watercontd Vitamin D (calciferol) 1 g calciferol 40 IU vitamin D DRI values are based on absence of adequate exposure to
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sunlight. Maintains serum calcium and phosphorus concentrations Infants (gday) Fish liver oils, flesh of fatty fish, liver, eggs from hens that have been fed vitamin D, fortified milk products, fortified cereals Elevated plasma 25(OH)D concentration causing hypercalcemia Patients receiving glucocorticoid therapy might require additional vitamin D.0 6 mo 10 25 7 12 mo 10 38 Children (gday) 1 3 yr 15 63 4 8 yr 15 75 Males (gday) 9 21 yr 15 100 Females (gday) 9 21 yr 15 100 Pregnancy (gday) 18 yr 15 100 Lactation (gday) 18 yr 15 100 19 21 yr 15 100 Calcium Essential role in blood clotting, muscle contraction, nerve transmission, and bone and tooth formation Infants Milk, cheese, yogurt, corn tortillas, calcium set tofu, Chinese cabbage, kale, broccoli Kidney stones, hypercalcemia, milk alkali syndrome, renal insufficiency Amenorrheic women (exercise or anorexia nervosa induced) have reduced net calcium absorption. 0 6 mo 200 1,000 7 12 mo 260 1,500 Children 1 3 yr 700 2,500 4 8 yr 1,000 2,500 Males 9 18 yr 1,300 3,000 19 21 yr 1,000 2,500 Females 9 18 yr 1,300 3,000 19 21 yr Pregnancy 18 yr 1,300 3,000 19 21 yr 1,000 2,500 Lactation 18 yr 1,300 3,000 19 21 yr 1,000 2,500 NUTRIENT FUNCTION LIFE STAGE GROUP AI (mgday) UL (mgday) SELECTED FOOD SOURCES ADVERSE EFFECTS OF EXCESSIVE CONSUMPTION SPECIAL CONSIDERATIONS Continued D ow nloaded for m oham ed ahm ed (dr.m m s2020 gm ail.com ) at U niversity of Southern C alifornia from C linicalK ey.com by Elsevier on A pril 20, 2024. For personal use only. N o other uses w ithout perm ission. C opyright 2024. Elsevier Inc. A ll rights reserved. 4 0 6 P art V u N utrition Iron Critical component of enzymes, cytochromes, myoglobin, and hemoglobin Infants Heme sources: meat, poultry, fish Nonheme sources: dairy, eggs, plant based foods like whole grains, nuts, seeds, legumes, and leafy greens, breads, cereals, breakfast foods GI distress Persons with decreased gastric acidity may be at increased risk for deficiency. Cows milk is a poor source of bioavailable iron and is not recommended for children 1 yr old. Neurocognitive deficits have been reported in infants with iron deficiency. RDA for females increases with menarche related to increased losses during menstruation. Vegans and vegetarians might require iron supplementation or intake of iron fortified foods. GI parasites can increase iron losses via GI bleeds. Iron supplements can interfere with zinc absorption, and vice versa; if supplements are being used, the doses should be staggered. 0 6 mo 0.27 40 7 12 mo 11 40 Children 1 3 yr 7 40 4 8 yr 10 40 Males 9 13 yr 8 40 14 18 yr 11 45 19 21 yr 8 45 Females 9 13 yr 8 40 14 18 yr 15 45 19 21 yr 18 45 Pregnancy 18 yr 27 45 19 21 yr 27 45 Lactation 18 yr 10 45 19 21 yr 9 45 Zinc Essential for proper growth and
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development; important catalyst for 100 specific enzymes Infants Meats, shellfish, legumes, fortified cereals, whole grains Acutely, zinc supplements cause GI irritation and headache; chronic effects of zinc supplementation include impaired immune function, changes in lipoprotein and cholesterol levels, and reduced copper status. Zinc supplements interfere with iron absorption, and vice versa; therefore if supplements are being used, the doses should be staggered. Zinc deficiency can be associated with stunting or impaired linear growth. 0 6 mo 2 4 7 12 mo 3 5 Children 1 3 yr 3 7 4 8 yr 5 12 Males 9 13 yr 8 23 14 18 yr 11 34 19 21 yr 11 40 Females 9 13 yr 8 23 14 18 yr 9 34 19 21 yr 8 40 Pregnancy 18 yr 12 34 19 21 yr 11 40 Lactation 18 yr 13 34 19 21 yr 12 40 Table 60.6 Dietary Reference Intakes for Select Micronutrients and Watercontd NUTRIENT FUNCTION LIFE STAGE GROUP AI (mgday) UL (mgday) SELECTED FOOD SOURCES ADVERSE EFFECTS OF EXCESSIVE CONSUMPTION SPECIAL CONSIDERATIONS D ow nloaded for m oham ed ahm ed (dr.m m s2020 gm ail.com ) at U niversity of Southern C alifornia from C linicalK ey.com by Elsevier on A pril 20, 2024. For personal use only. N o other uses w ithout perm ission. C opyright 2024. Elsevier Inc. A ll rights reserved. C hap ter 6 0 u N utritio nal R eq uirem ents 4 0 7 Water Maintains homeostasis in the body Allows transport of nutrients to cells and removal and excretion of waste products of metabolism Infants (Lday) All beverages, including water Moisture in foods High moisture foods include watermelon, meats, and soups No UL because normally functioning kidneys can handle 0.7 L (24 oz) of fluid per hour. Symptoms of water intoxication include hyponatremia, which can result in heart failure, and rhabdomyolysis (skeletal muscle tissue injury), which can lead to kidney failure. Recommended intakes for water are based on median intakes of generally healthy persons who are adequately hydrated. Persons can be adequately hydrated at levels above or below the AIs provided; AIs provided are for total water in temperate climates. All sources can contribute to total water needs: beverages (tea, coffee, juice, soda, drinking water) and moisture found in foods. Moisture in food accounts for about 20 of total water intake. Thirst and consumption of beverages at meals are adequate to maintain hydration. 0 6 mo 0.7 None set 7 12 mo 0.8 Children 1 3 yr 1.3 4 8 yr 1.7 Males (Lday) 9 13 yr 2.4 14 18 yr 3.3 19 yr 3.7 Females (Lday) 9 13 yr 2.1 14 18 yr 2.3 19 yr 2.7 Pregnancy (Lday) 14 yr 3.0 Lactation (Lday) 14 yr 3.8 Note: Bold numbers are RDA. RDAs and AIs may both be used as goals for individual intake. RDAs are set to meet the needs of 9798 of members in a group. For healthy breastfed infants, the AI is the mean
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intake. The AI for other life stage and gender groups is believed to cover the needs of all members of a group, but lack of data prevents specifying with confidence the percentage covered by this intake. UL is the maximum level of daily nutrient intake that is likely to pose no risk of adverse effects. Unless otherwise specified, the UL represents total intake from food, water, and supplements. Because of a lack of suitable data, ULs could not be established for potassium, water, or inorganic sulfate. In the absence of ULs, extra caution may be warranted in consuming levels above recommended intakes. ND amounts are not determinable because of a lack of data on adverse effects in this age group and concern with regard to lack of ability to handle excess amounts. Source of intake should be from food only to prevent high levels of intake. Vitamin D RDA in IUday: 400 if 1 yr, 600 if 1 yr of age or pregnant or lactating. ACE, Angiotensin converting enzyme; AI, adequate intake; ARB, angiotensin receptor blocker; GI, gastrointestinal; ND, not determinable; RDA, recommended dietary allowance; UL, upper limit of normal. Data from Food and Nutrition Board, U.S. Institute of Medicine. Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate (http:www.nap.eduopenbook.php?recordid10925); and Ross AC, U.S. Institute of Medicine, Committee to Review Dietary Reference Intakes for Vitamin D and Calcium. Dietary Reference Intakes: Calcium, Vitamin D. Washington, DC: National Academies Press; 2011: pp. xv, 536 Table 60.6 Dietary Reference Intakes for Select Micronutrients and Watercontd D ow nloaded for m oham ed ahm ed (dr.m m s2020 gm ail.com ) at U niversity of Southern C alifornia from C linicalK ey.com by Elsevier on A pril 20, 2024. For personal use only. N o other uses w ithout perm ission. C opyright 2024. Elsevier Inc. A ll rights reserved. 408 Part V u Nutrition infants and young children can be explained in part by the high ratio of body surface area to volume in infancy, high respiratory rate, and rapid growth. The consequences of inadequate fluid intake include impaired ther moregulation and heat dissipation, reduced activity tolerance and per formance, and reduced intravascular fluid and dehydration. Inadequate fluid intake may be reflected by decreased urine output. These defi cits can result in an increased compensatory heart rate, hypotension, and syncope, and if uncorrected, renal injury or nephrolithiasis. Free water is defined as water in the body that can be removed by ultra filtration and in which substances can be dissolved. Excess free water intake is usually better tolerated by healthy adults than by younger chil dren, who are at increased risk for water intoxication. Hyponatremia can result when water and sodium are out of balance, such as excess free water intake coupled with inadequate sodium intake. Fluid intake requirements and restrictions are also influenced by any underlying renal and hormonal disorders, including diabetes, the syndrome of inappropriate antidiuretic hormone secretion (SIADH), and diabetes insipidus. MEASURING NUTRITIONAL ADEQUACY The U.S. Centers for
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Disease Control and Prevention (CDC) and AAP recommend the use of the WHO charts to monitor growth of all infants and children (human milkfed and infant formulafed) from birth to 2 years, and the use of the CDC 2000 growth charts for children 2 20 years (see Chapters 19 and 27). The WHO growth charts are derived from longitudinal and cross sectional data obtained from a sample of healthy breastfed infants and children (0 2 years) who were receiving adequate nutritional intake and medical care in Brazil, Ghana, India, Norway, Oman, and the United States. Consequently, the WHOCDC 0 2 year growth charts are considered standards and describe the ideal growth of adequately nourished healthy children under best care prac tices. The CDC 2 20 year charts are considered references and describe the populations average growth and distribution. In the clinical setting, the 2.3rd and 97.7th percentiles on the WHO growth charts are used to identify insufficient and excessive growth from birth to 2 years, respectively. In contrast, the 5th and 95th percentiles are recommended for the equivalent identification in the CDC growth charts from 2 to 20 years (Table 60.7). Note that length, weight, and 2 2 4 Other Sandwiches 7 31 Burritos Tacos Other Sources 19 Sandwiches 21 Rice, Pasta Other GrainBased Mixed Dishes 8 Vegetables, Excluding Starchy 7 Pizza 5 Poultry, Excluding Deli Mixed Dishes 5 Meat, Poultry Seafood Mixed Dishes 5 Desserts Sweet Snacks 4 Starchy Vegetables 4 Soups 4 Yeast Breads Tortillas 3 Eggs 3 Condiments Gravies 3 Breakfast Cereals Bars 3 Chips, Crackers Savory Snacks 4 Deli Cured Products 3 Chicken Turkey Sandwiches Breakfast Sandwiches Hotdog Sandwiches PBJ Sandwiches Pasta Mixed Dishes, Excludes Macaroni Cheese Other Mexican Dishes, Excludes Tacos Burritos Rice Mixed Dishes 3 1 1 Within Sandwiches: Within Rice, Pasta Other GrainBased Mixed Dishes: Other Sources 3 Other Sources 2 Sodium Average Intake: 3,393 mgday Fig. 60.5 Top sources and average intakes of sodium: U.S. population age 1 and older. Estimates based on 2 day dietary intake data, weighted, from What We Eat in America (WWEIA), National Health and Nutrition Examination Survey (NHANES), 2013 2016. (From Dietary Guidelines for Americans. 2020 2025, Chapter 1: Nutrition and Health Across the Lifespan. Fig 1.12. https:www.dietaryguidelines.govsitesdefaultfiles2020 12DietaryGuidelinesforAmericans2020 2025.pdf.) Table 60.7 Growth Chart Comparisons for Measuring Growth from Birth to 20 Years GROWTH CHART AGE RANGE GROWTH METRICS INSUFFICIENT GROWTH PERCENTILE EXCESSIVE GROWTH PERCENTILE BMI STATUS PERCENTILE World Health Organization, 2006 Birth to 2 yr Weight, length, weight for length, and head circumference 2.3rd 97.7th U.S. Centers for Disease Control and Prevention, 2000 2 20 yr Weight, height, body mass index (BMI) 5th 95th Under (5th) Normal (5 85th) Over (85 95th) Obese (95th) Severe obesity (120 of 95th or 35 kgm2) Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 61 u Feeding Healthy Infants, Children, and Adolescents 409
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weight for length are used in the WHO growth charts from birth to 2 years. Body mass index (BMI) can be calculated but is not recommended for use in children 2 years. Stature, weight, and BMI are used in the CDC 2000 growth charts from 2 to 20 years of age. These charts can be used to categorize children as underweight (5th BMI percentile), normal weight (5 85th), overweight (85 95th), and obese (95th BMI percentile). Severe obesity is defined as BMI 120 of the 95th percentile or BMI 35 kgm2 (whichever is lower). This assessment corresponds to approximately the 99th percentile or a BMI z score 2.33. Severe obe sity that exceeds the 99th percentile is tracked on a specialized percen tile curve for obesity. Furthermore, adult classification is used for BMI 27 kgm2 in adolescents over age 18 for consideration of medication and bariatric surgery. It is important to consider the limitations in the use of WHO and CDC growth charts for certain populations such as premature infants, children with certain genetic disorders (e.g., Turner syndrome, Down syndrome, Wolf Hirschhorn syndrome, achondroplasia) and chil dren with cerebral palsy. Specific growth charts addressing the unique growth characteristics of these children are available from various resources, including the AAP. Visit Elsevier eBooks at eBooks.Health.Elsevier.com for Bibliography. Early feeding experiences can support the development of healthy eating habits, optimal growth and development, and prevention of chronic disease throughout the life course. Childhood nutrition is known to play a role in the origin of adult diseases such as type 2 diabe tes, hypertension, obesity, and metabolic syndrome. To support devel opment and to prevent chronic disease, appropriate feeding practices are best established in the neonatal period and continued throughout childhood and adolescence to adulthood. Healthful feeding in children requires partnerships between family members, the healthcare system, schools, the community, and policy makers. FEEDING DURING THE FIRST YEAR OF LIFE Breastfeeding The American Academy of Pediatrics (AAP) and World Health Orga nization (WHO) have declared breastfeeding and the administration of human milk to be the ideal practice for infant feeding and nutrition. Breastfeeding has documented short and long term medical and neu rodevelopmental advantages and rare contraindications (Tables 61.1, 61.2, and 61.3). The AAP and the WHO recommend that infants be exclusively fed human breast milk for approximately 6 months. Breast feeding ideally should be continued with the introduction of comple mentary foods until 24 months of age or longer, if mutually desired by the mother and infant. We recognize that there are some lactating indi viduals who do not identify as womenmothers and may prefer the use of other terms, including the use of chestfeeding in lieu of breastfeed ing. This is a consideration that a practitioner may need to make when speaking to a family member who uses these alternative terms. The suc cess of breastfeeding initiation and continuation depends on multiple Chapter 61 Feeding Healthy Infants, Children, and Adolescents Katherine J. Barrett, Stephanie P. Gilley, Matthew A. Haemer, Nancy F.
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Krebs, and Susan L. Johnson factors, such as education about breastfeeding, hospital breastfeeding practices and policies, routine and timely follow up care, family and societal support, and the health of the mother (Tables 61.4 and 61.5). Breastfeeding support from both professionals and lay individuals has a positive impact on breastfeeding success, and the importance of such support cannot be overstated. Feedings are initiated soon after birth unless medical conditions preclude them. Mothers can be encouraged to feed at both breasts at each feeding, starting with the breast offered second at the last feeding. For optimal milk production, it is preferable to fully empty the first breast before moving to the second breast, rather than par tially emptying both sides. It is not unusual for an infant to fall asleep after the first breast and refuse the second. Table 61.6 summarizes patterns of milk supply in the first week. Pacifiers may help prevent sudden infant death syndrome in breastfed infants, but it is not rec ommended to introduce until breastfeeding is well established and should not be used to try to increase time between feeds or in lieu of a feed in a baby showing hunger cues. Breastfeeding is a learned skill for both mother and infant, and support from a provider knowledgeable in breastfeeding is critical, especially as milk production is established in the first few weeks post partum. It is helpful to instruct new mothers about infant hunger cues and correct nipple latch, positioning of the infant on the breast, and feeding frequency. It is also suggested that someone trained in lactation observe a feeding to evaluate positioning, latch, milk transfer, maternal responses, and infant satiety. Attention to these issues during the new born period allows dialog with the mother and family and can prevent problems that could occur with improper technique or knowledge of breastfeeding. Discussions about normal infant feeding, infant elimina tion patterns, breast engorgement, breast care, and maternal nutrition are important aspects of the hospital discharge process. A follow up appointment with a lactation specialist is recommended within 24 48 hours after hospital discharge. The AAP recommends that exclusively breastfed infants start supplementation with vitamin D (10 mcg, or 400 IU) by 2 weeks of life. Table 61.1 Selected Beneficial Properties of Human Milk Compared with Infant Formula FACTOR ACTION ANTIBACTERIAL FACTORS Secretory IgA Specific antigen targeted antiinfective action Lactoferrin Immunomodulation, iron chelation, antimicrobial action, antiadhesive, trophic for intestinal growth Casein Antiadhesive, bacterial flora Oligosaccharides Prevention of bacterial attachment Cytokines Antiinflammatory, epithelial barrier function GROWTH FACTORS Epidermal growth factor Luminal surveillance, repair of intestine Transforming growth factor (TGF) Promotes epithelial cell growth (TGF ) Suppresses lymphocyte function (TGF ) Nerve growth factor Promotes neural growth ENZYMES Platelet activating factor (PAF)acetylhydrolase Blocks action of PAF Glutathione peroxidase Prevents lipid oxidation Nucleotides Enhance antibody responses, bacterial flora Adapted from Hamosh M. Bioactive factors in human milk. Pediatr Clin North Am. 2001;48:6986. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20,
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2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 410 Part V u Nutrition Table 61.2 Absolute and Relative Contraindications to Breastfeeding Because of Maternal Health Conditions MATERNAL HEALTH CONDITION DEGREE OF RISK HIV and HTLV infection In the United States, breastfeeding is contraindicated. In other settings, health risks of not breastfeeding must be weighed against the risk of transmitting the virus to the infant. Tuberculosis infection Direct breastfeeding is contraindicated until completion of approximately 2 wk of appropriate maternal therapy. Varicella zoster infection Infant should not have direct contact with active lesions. Infant should receive immune globulin. Herpes simplex infection Breastfeeding is contraindicated with active herpetic lesions of the breast. CMV infection May be found in milk of mothers who are CMV seropositive. Transmission through human milk causing symptomatic illness in term infants is uncommon. Hepatitis B infection Infants routinely receive hepatitis B immune globulin and hepatitis B vaccine if mother is HBsAg positive. No delay in initiation of breastfeeding is required. Hepatitis C infection Breastfeeding is not contraindicated. COVID 19 Maternal infection is not a contraindication for breastfeeding or feeding expressed milk. Ebola Confirmed maternal Ebola infection is a contraindication to breastfeeding and expressed milk. Brucellosis Active untreated brucellosis is a contraindication to breastfeeding and expressed milk. Live vaccines Smallpox and yellow fever live virus vaccines are contraindicated for breastfeeding mothers. Alcohol intake Limit maternal alcohol intake to 0.5 gkgday (for a woman of average weightthis is the equivalent of 2 cans of beer, 2 glasses of wine, or 2 oz of liquor). Cigarette smoking Discourage cigarette smoking, but smoking is not a contraindication to breastfeeding. Marijuana usage Metabolites, including tetrahydrocannabinol, are detectable in breast milk. Marijuana usage is not recommended but is not a strict contraindication to breastfeeding. Chemotherapy, radio pharmaceuticals Breastfeeding is generally contraindicated. CMV, Cytomegalovirus; HBsAg, hepatitis B surface antigen; HIV, human immunodeficiency virus; HTLV, human T lymphotropic virus. Adapted from Schanler RJ, Krebs NF, Mass SB (eds). Breastfeeding Handbook for Physicians, 2nd ed. Elk Grove Village, IL: American Academy of Pediatrics; 2014: 223226. Nipple pain is one of the most common complaints of breastfeeding mothers in the immediate postpartum period. Poor infant position ing and improper latch are the most common reasons for nipple pain beyond the mild discomfort felt early in breastfeeding. If the problem persists and the infant refuses to feed, evaluation for nipple candidia sis is indicated. If candidiasis is present, the nipples can be treated with an antifungal cream that is wiped off of the breast before feeding, and the infant is treated with an oral antifungal medication. Tongue tie (ankyloglossia) has been associated with nipple pain, poor latching, and poor weight gain in breastfed and bottle fed infants. Ankyloglossia is defined as a lingual frenulum that attaches close to the anterior tongue tip and is estimated to be present in 411 of new borns. Frenotomy is a minor surgical procedure with few complications Table 61.3 Conditions for Which Human Milk May
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Have a Protective Effect INFANT MOTHER Diarrhea Otitis media Urinary tract infection Necrotizing enterocolitis Septicemia Infant botulism Insulin dependent diabetes mellitus Celiac disease Crohn disease Lymphoma Leukemia Recurrent otitis media Atopy Hospitalizations for respiratory illness Sudden infant death syndrome Obesity Uterine atony Breast cancer Ovarian cancer Cardiovascular disease Obesity Type 2 diabetes Table 61.4 Ten Hospital Practices to Encourage and Support Breastfeeding 1. Have a written breastfeeding policy that is routinely communicated to all healthcare staff. 2. Train all healthcare staff in the skills necessary to implement this policy. 3. Inform all pregnant women about the benefits and management of breastfeeding. 4. Help women initiate breastfeeding within 1 hour of birth. 5. Show women how to breastfeed and how to maintain lactation, even if they are separated from their newborns. 6. Give newborns no food or drink other than breast milk unless medically indicated. 7. Practice rooming in; allow mothers and newborns to remain together 24 hours a day. 8. Encourage breastfeeding on demand. 9. Give no pacifiers or artificial nipples to breastfeeding infants. 10. Foster the establishment of breastfeeding support groups and refer to them on discharge from the hospital or birth center. COMPONENTS OF SAFE POSITIONING FOR THE NEWBORN WHILE SKIN TO SKIN 1. Infants face can be seen. 2. Infants head is in sniffing position. 3. Infants nose and mouth are not covered. 4. Infants head is turned to one side. 5. Infants neck is straight, not bent. 6. Infants shoulders and chest face mother. 7. Infants legs are flexed. 8. Infants back is covered with blankets. 9. Mother infant dyad is monitored continuously by staff in the delivery environment and regularly on the postpartum unit. 10. When mother wants to sleep, infant is placed in bassinet or with another support person who is awake and alert. The 1994 report of the Healthy Mothers, Healthy Babies National Coalition Expert Work Group recommend that the UNICEF WHO Baby Friendly Hospital Initiative be adapted for use in the United States as the United States Breastfeeding Health Initiative, using the adapted 10 hospital practices noted. Data from Baby Friendly USA. Guidelines and evaluation criteria for facilities seeking baby friendly designation. Sandwich, MA: Baby Friendly USA; 2010. Available at https:www.b abyfriendlyusa.orgfor facilitiespractice guidelines. Accessed 10 November 2022. From ACOG Committee Opinion. Optimizing support for breastfeeding as part of obstetric practice. Obstet Gynecol. 2018;132(4):e187e195, Boxes 1 and 2, pp. e191e192. The American Academy of Pediatrics endorsed the UNICEF WHO Ten Steps to Successful Breastfeeding, but does not support a categorical ban on pacifiers because of their role in reducing the risk of sudden infant death syndrome and their analgesic benefit during painful procedures when breastfeeding cannot provide the analgesia. Data from Ludington Hoe SM, Morgan K. Infant assessment and reduction of sudden unexpected postnatal collapse risk during skin to skin contact. Newborn Infant Nurs Rev. 2014;14:2833. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without
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permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 61 u Feeding Healthy Infants, Children, and Adolescents 411 and has been used as a treatment option for ankyloglossia with increas ing frequency despite insufficient evidence that it improves breastfeed ing outcomes, making its use somewhat controversial. Most infants with ankyloglossia have no feeding problems, and most infants with nursing problems do not have ankyloglossia. Providing a feeding evaluation and assessment of latch while monitoring weight over the course of 2 3 weeks may be more valuable than proceeding immedi ately to frenotomy. During that time many feeding issues resolve, thus avoiding unnecessary frenotomy. Engorgement may occur in the second stage of lactogenesis (typi cally days 3 10 postpartum) and is characterized by the breasts feeling firm, overfilled, and sometimes painful. Incomplete removal of milk as a result of ineffective breastfeeding technique or infant illness can cause engorgement. Breastfeeding immediately at signs of infant hunger can prevent this from occurring. To reduce engorgement, breasts may be softened before infant feeding with a combination of hot compresses and manual expression of milk. To reduce inflamma tion and pain, between feedings mothers can wear a supportive bra, apply cold compresses, and take oral nonsteroidal antiinflammatory drugs (NSAIDs). Mastitis occurs in 23 of lactating women and is usually unilateral, manifesting with localized warmth, tenderness, edema, and erythema after the second postdelivery week. Sudden onset of breast pain, myal gia, and fever with fatigue, nausea, vomiting, and headache can also occur. Organisms implicated in mastitis include Staphylococcus aureus, Escherichia coli, group A streptococcus, Haemophilus influenzae, Kleb siella pneumoniae, and Bacteroides species. Diagnosis is confirmed by physical examination. Treatment is with oral antibiotics (most com monly dicloxacillin or cephalexin) and analgesics, while at the same time promoting breastfeeding or emptying of the affected breast. A breast abscess is a much less common complication of mastitis, but it is a more serious infection that requires intravenous antibiotics and incision and drainage, along with continued breast emptying. Wash ing hands thoroughly before breastfeeding or pumping, especially after changing the babys diapers, can help minimize risk for breast infections. Insufficient milk intake, dehydration, and jaundice in the infant can occur within the first weeks of life. In fact, retrospective studies suggest higher rates of hospitalizationprimarily caused by jaundice and poor weight gainin the first month of life for breastfed versus formula fed babies, highlighting the critical importance of lactation support. Breastfed neonates feed 8 12 times a day. Signs that milk intake is not adequate include lethargy, delayed stooling, decreased urine output, weight loss 10 of birthweight, hypernatremic dehydration, incon solable crying, and increased hunger. Insufficient milk intake may be caused by inadequate milk production andor health conditions in the infant that prevent proper breast stimulation. Careful attention to prenatal history can identify maternal factors associated with low milk production (for example, obesity, type 2 diabetes, postpartum hemor rhage, or failure of breasts to enlarge during pregnancy or within the first few days after delivery). Excess weight loss or
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failure to return to birthweight by 7 10 days in an exclusively breastfed infant should trig ger an evaluation of breastfeeding effectiveness. Direct observation of breastfeeding can help identify improper technique, and test weighs (weighing the infant before and after feeding) may help assess milk transfer. If a large volume of milk is expressed manually after breast feeding, the infant might not be extracting enough milk, eventually leading to decreased milk output. Late preterm infants (34 36 weeks) are at particular risk for insufficient milk intake because of weak suck, difficulty coordinating suck and swallow patterns, or medical issues. Breastfeeding jaundice, also referred to as suboptimal intake jaun dice, is related to insufficient fluid intake during the first week of life and is a common reason for hospital readmission of healthy breast fed infants (see Chapter 137). Breastfeeding jaundice is associated with dehydration and hypernatremia. Treatment may require supple mentation with expressed maternal breast milk, donor milk, or infant formula. Breast milk jaundice is a different disorder that causes per sistently high serum indirect bilirubin in thriving, healthy, well fed infants. Breast milk contains inhibitors of glucuronyl transferase and causes enhanced absorption of bilirubin from the gut. Breast milk jaundice becomes evident later than breastfeeding jaundice and gen erally declines in the second to third week of life. Infants with severe or persistent jaundice or a direct hyperbilirubinemia need evaluation for other medical causes (see Chapter 137). Persistently high bilirubin levels may require treatment with phototherapy without cessation of breastfeeding or changing from breast milk to infant formula for 24 48 hours if phototherapy is not available or if a rapid reduction in total serum bilirubin is urgently needed. Breastfeeding can resume after the decline in serum bilirubin. Parents can be encouraged to continue col lecting breast milk during the period the infant is taking formula. Table 61.5 Recommendations on Breastfeeding Management for Healthy Term Infants 1. Exclusive breastfeeding for about 6 months Breastfeeding preferred; alternatively, expressed mothers milk or donor breast milk To continue for 2 years or beyond as long as mutually desired by mother and child Complementary foods rich in iron, zinc, and other micronutrients should be introduced at about 6 mo of age 2. Peripartum policies and practices that optimize breastfeeding initiation and maintenance should be compatible with the AAP and Academy of Breastfeeding Medicine Model Hospital Policy and include the following: Direct skin to skin contact with mothers immediately after delivery until the first feeding is accomplished and encouraged throughout the postpartum period Delay in routine procedures (weighing, measuring, bathing, blood tests, vaccines, and eye prophylaxis) until after the first feeding is completed Delay in administration of intramuscular vitamin K until after the first feeding is completed but within 6 hr of birth Ensure 8 12 feedings at the breast every 24 hr Ensure formal evaluation and documentation of breastfeeding by trained caregivers (including position, latch, milk transfer, examination) at least once for each nursing shift Give no supplements (water, glucose water, commercial infant formula,
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or other fluids) to breastfeeding newborn infants unless medically indicated using standard evidence based guidelines for the management of hyperbilirubinemia and hypoglycemia Avoid routine pacifier use in the postpartum period Begin daily oral vitamin D drops (400 IU) at hospital discharge 3. All breastfeeding infants should be seen by a pediatrician within 48 72 hr after discharge from the hospital Evaluate hydration and elimination patterns If weight 7 below birthweight or there is additional weight loss on day 5 or later, providers should consider more frequent followups and or referral to a lactation consultant. Discuss maternalinfant issues Observe feeding 4. Mother and infant should sleep in proximity to each other to facilitate breastfeeding 5. Pacifier should be offered, while placing infant in back to sleep position, no earlier than 3 4 weeks of age and after breastfeeding has been established From American Academy of Pediatrics (AAP). Breast feeding and the use of human milk. Pediatrics. 2012;129:e827e841. Table 61.6 Patterns of Milk Supply DAY OF LIFE MILK SUPPLY Day 1 Some milk (5 mL) may be expressed. Days 2 4 Lactogenesis; milk production increases. Day 5 Milk present; fullness and leaking are felt. Day 6 onward Breasts should feel empty after feeding. Adapted from Neifert MR. Clinical aspects of lactation: promoting breastfeeding success. Clin Perinatol. 1999;26:281306. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 412 Part V u Nutrition Breast milk collection by pumping is a common practice when the mother and baby are separated and when families wish for other care givers to engage in infant feeding. Electric breast pumps are generally more efficient and better tolerated by mothers than manual pumps or hand expression, but not all insurance companies cover electric pumps. Good handwashing and hygiene are important during all steps of pumping. Collection kits should be cleaned with hot soapy water, rinsed, and air dried after each use. Glass or plastic containers can be used to collect the milk. Fresh milk can be stored at room temperature for up to 4 hours and in the refrigerator for up to 4 days. Expressed breast milk can be frozen and used for up to 6 12 months; frozen milk should be used within 24 hours of thawing. Human milk should never be microwaved. Paced bottle feeding helps support breastfeeding dur ing bottle feeds by matching the slower pace of direct breastfeeding. Growth of the breastfed infant differs from that of the formula fed infant; the infants risk for excess weight gain during late infancy may be associated with bottle feeding (whether formula or expressed human milk). The WHO growth charts are based on growth patterns of healthy breastfed infants through the first year of life. The infants were selected based on being breastfed, having good healthcare, an absence of socioeconomic constraints, and nonsmoking mothers, so that they reflect the growth pattern of breastfed infants
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in optimal conditions and can be used as prescriptive standards rather than as normative ref erence curves. Charts are available for growth monitoring. The Centers for Disease Control and Prevention (CDC) recommends use of the WHO growth charts for infants from birth to 2 years and CDC growth charts for ages 2 to 20 years (see Chapter 27). Formula Feeding Despite efforts to promote exclusive breastfeeding through 6 months, only 55 of women in the United States continue any breastfeeding at 6 months. Parental preferences are the most common reason for using infant formula and may relate to return to work, perceived poor milk supply, lack of support, or other factors. Most parents make their infant feeding choices early in pregnancy. However, infant formula is also indicated for infants whose intake of breast milk is contraindicated for infant factors (e.g., inborn errors of metabolism) or maternal factors (see Table 61.2). In addition, infant formula may be used as a supple ment to support inadequate weight gain in breastfed infants, though often formula is used to supplement based upon caregiver perception of benefit rather than medical necessity. Infant formulas marketed in the United States are safe and nutrition ally adequate as the sole source of nutrition for healthy infants for the first 6 months of life. Infant formulas are available in ready to feed, concentrated liquid, and powder forms. Ready to feed products gener ally provide 19 20 kcal30 mL (1 oz) and approximately 64 67 kcal100 mL. Concentrated liquid products, when diluted according to instruc tions, and powder formulas, when mixed according to instructions (typically 2 ounces of water plus one scoop of powder), will result in similar caloric density. Although infant formulas are manufactured in adherence to good manufacturing practices and are regulated by the U.S. Food and Drug Administration (FDA), there are potential safety issues. Ready to feed and concentrated liquid formulas are commercially sterile, but pow der preparations are not. Although the number of bacterial colony forming units per gram (CFUg) of powder formula is generally lower than allowable limits, outbreaks of infections with Cronobacter sakazakii (previously Enterobacter sakazakii) have been documented, especially in premature infants. The powder preparations can contain other coliform bacteria but have not been linked to disease in healthy term infants. Care must be taken to follow the mixing instructions to avoid overdilution or underdilution, to use clean water, and to use the specific scoops provided by the manufacturer because scoop sizes vary. Water that has been boiled must cool fully to prevent degrada tion of heat labile nutrients, specifically vitamin C. Well water should be tested regularly for bacteria and toxin contamination. Testing may also identify high lead concentrations in water flowing through pipes installed before 1986. Municipal water can contain variable concentra tions of fluoride, and if the concentrations are higher than 2.0 mgL, use of bottled water that is defluoridated is preferred to avoid possible toxicity and tooth discoloration. Proper handwashing is important before preparing formula for the infant. Formula
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storage guidelines vary based on preparation. Once opened, ready to feed and concentrated liquid containers can be covered and stored in the refrigerator for no longer than 48 hours. Manufacturer guidelines recommend storing powder formula in a cool, dry place but not in the refrigerator; once opened, cans can be covered with the original plastic cap or aluminum foil, and the pow dered product used within 4 weeks. The CDC recommends using pre pared formula within 24 hours, regardless of type. The CDC further recommends using formula within 2 hours of removal from the refrig erator and within 1 hour from the start of a feed. Prepared formula stored in the refrigerator can be warmed by placing the container in warm water for about 5 minutes. Formula should never be heated in a microwave because it can heat unevenly and result in burns, despite appearing to be at the right temperature when tested. Formula feedings are ideally provided ad libitum, with the goal of achieving growth and development to the childs genetic potential. The usual intake to allow a weight gain of 20 30 gday in the first 2 3 months of life is approximately 140 180 mLkgday, although some may require intake outside this range. The average rate of weight gain declines from 3 to 12 months of age (see Chapters 27 and 64). Over feeding with resultant rapid weight gain increases the risk for develop ing obesity and is to be prevented. Paced bottle feeding may help avoid overfeeding. COWS MILK PROTEINBASED FORMULAS Intact cows milk proteinbased formulas are appropriate for most term infants. There are nutritional differences between formula and breast milk, although the effects of these differences on long term health are unknown. Formulas contain 10 35 times higher iron com pared with breast milk and higher zinc, sodium, and vitamin D. Most formulas in the United States also contain considerably higher protein than in mature breast milk. This concentration is designed to meet the needs of the youngest infants but may lead to excess protein intake for older infants and has been associated with increased risk of obesity. In contrast, breast milk protein content decreases over time to match needs. Protein concentration and composition differences between human milk and cows milkbased formulas result in different plasma amino acid profiles in infants on different feeding patterns, but clinical significance has not been demonstrated. Fat provides 4050 of the energy in cows milkbased formulas and is primarily from plant and animal oils. Fat blends are better absorbed than dairy fat and provide saturated, monounsaturated, and polyun saturated fatty acids (PUFAs). All infant formulas are supplemented with long chain PUFAs, specifically docosahexaenoic acid (DHA) and arachidonic acid (ARA). DHA and ARA are found at varying concen trations in human milk and vary by geographic region and maternal diet. The DHA and ARA added to formulas are derived from single cell microfungi and microalgae and are classified as generally recognized as safe (GRAS) for use in infant formulas at
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approved concentrations and ratios. Long term studies are lacking on the relationship between routine supplementation of formula with long chain PUFAs and physi cal, neurodevelopmental, or visual outcomes of term infants. Lactose is the major carbohydrate in breast milk and in standard cows milkbased formulas for term infants. Formulas for term infants may also contain modified starch or other complex carbohydrates like prebiotic oligosaccharides similar to those in human milk. SOY PROTEINBASED FORMULAS Soy proteinbased formulas on the market are all free of cows milkbased protein and lactose. They meet the vitamin, mineral, and electrolyte guidelines from the AAP and the FDA for feeding term infants. In term infants, although soy proteinbased formulas have been used to provide nutrition resulting in normal growth pat terns, there are few indications for use in place of cows milkbased formula. Indications for soy formula include galactosemia, prefer ence for a vegetarian diet, and hereditary lactase deficiency, because Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 61 u Feeding Healthy Infants, Children, and Adolescents 413 soy based formulas are lactose free. Most healthy infants with acute gastroenteritis can be managed after rehydration with continued use of breast milk or cows milkbased formulas and do not require a lactose free formula. However, soy proteinbased formulas may be indicated when documented secondary lactose intolerance occurs. Soy proteinbased formulas have no advantage over cows milk pro teinbased formulas as a supplement for the breastfed infant, unless the infant has one of the indications noted previously. Soy protein based formulas are contraindicated for preterm infants because of concerns about protein quality and aluminum content. The rou tine use of soy proteinbased formula has no proven value in the prevention or management of infantile colic, fussiness, or atopic disease. Infants with documented cows milk proteininduced enteropathy or enterocolitis often are also sensitive to soy protein and should be fed using an extensively hydrolyzed or amino acid based formula. PROTEIN HYDROLYSATE FORMULAS Protein hydrolysate formulas may be partially hydrolyzed, contain ing oligopeptides with a molecular weight of 5,000 daltons (range 3,000 10,000 Da), or extensively hydrolyzed, containing peptides with a molecular weight 3,000 Da. These formulas are lactose free and can include medium chain triglycerides, making them use ful in infants with gastrointestinal malabsorption caused by cystic fibrosis, short bowel syndrome, prolonged diarrhea, or hepatobili ary disease. Partially hydrolyzed protein formulas have fat blends similar to cows milkbased formulas, and carbohydrates are sup plied by corn maltodextrin or corn syrup solids. Because the pro tein is only partially hydrolyzed, these formulas are not appropriate for infants who are allergic to cows milk protein. There is insuf ficient evidence to recommend use of hydrolyzed formulas to pre vent atopic dermatitis or other atopic diseases in high risk infants. Extensively hydrolyzed formulas are recommended for infants intolerant to cows milk or soy proteins. AMINO ACID
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FORMULAS Amino acid (elemental) formulas are peptide free formulas that con tain mixtures of essential and nonessential amino acids. They are designed for infants with cows milkbased protein allergy who fail to thrive on extensively hydrolyzed protein formulas. The effective ness of amino acid formulas to prevent atopic disease has not been studied. OTHER FLUIDS IN INFANTS AND TODDLERS Neither breastfed nor formula fed infants require additional water unless dictated by a specific condition involving excess water loss, such as diabetes insipidus. Vomiting and spitting up are common in healthy infants. When weight gain and general well being are noted, no change in formula is necessary. Whole cows milk can impair iron absorption and is not recommended for infants younger than 12 months. Nondairy, very low protein milks are also inadequate to meet infant nutritional needs. Prune or apple juice may be used in small amounts for treatment of constipation, but juice is not recom mended for routine consumption in infants. Infants with vomiting caused by gastroenteritis may need to consume an oral electrolyte solution but will need close monitoring and ideally will consume the solution for less than 24 hours. Goat milk is not an appropriate substitution for formula. Goat milk has been shown to cause sig nificant electrolyte disturbances and anemia because it has low folic acid concentrations. Likewise, homemade formulas, which typically involve a combination of raw cow, raw goat, or plant based milk, cod liver oil, molasses, and other ingredients, cannot be considered safe for infant feeding. Mixing homemade formula incorrectly can put unnecessary stress on a newborns kidneys and intestines and may not provide sufficient calories or micronutrients. Infants and young children are also particularly susceptible to infections such as Escherichia coli, Campylobacter, Listeria, Brucella, and Salmo nella found in raw or unpasteurized milk. COMPLEMENTARY FEEDING The timely introduction of complementary foods (solid and liquid foods other than breast milk or formula, also called weaning foods) during infancy is important for nutritional and developmental reasons (Table 61.7). The AAP recommends exclusive breastfeeding for about the first 6 months, after which nutrient requirements cannot be met by breastfeeding alone. Table 61.7 summarizes the AAP recommen dations for introducing complementary foods, though nearly 25 of parents do not adhere to current guidelines (e.g., introducing comple mentary foods too early or introducing inappropriate foods, such as cows milk, in children under 12 months). Complementary foods should be introduced around 6 months and be varied to ensure adequate macronutrient and micronutrient intake. Although there is not currently evidence to promote a rec ommended order in which to introduce foods, information about important nutrients is included here. Additionally, a wide variety of textures is important for oral motor development, typically starting with pureed or very soft (easy to mash with the gums) foods. This is also a good time to establish consistent eating routines, including providing predictable meal and snack times for solid foods, eating in a safe dedicated space (such as in a highchair at the family table), and
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eating with family members to the extent possible. Continued breastfeeding up to 24 months of age and use of infant formula until 12 months is encouraged. Some complementary foods are more nutritionally beneficial than others. Iron and zinc rich foods (such as fortified infant cereals, age appropriate meats, eggs, and legumes) are especially important for breastfed infants, whose iron and zinc stores decline over time and are not sufficiently replaced through consumption of breast milk. Yogurt and cheese (including soy based products) without added sugars are appropriate for infants receiving complementary foods, but full fat cows milk as a replacement for infant milk is inappropriate before 12 months. In addition to honey and unpasteurized consumables, foods and beverages with added sugars and those high in sodium are not rec ommended. Overconsumption of energy dense complementary foods (e.g., cakes, cookies, fried foods, and sugar sweetened beverages) can lead to excessive weight gain in infancy, increasing the risk of obesity in childhood. Early introduction of peanuts and eggs around 4 6 months helps to prevent the development of food allergies. Although data are limited for other highly allergenic foods, the strength of current evidence sug gests that introducing other allergenic foods early in complementary Table 61.7 Important Principles for Weaning Begin around 6 mo of age. Introduce one new food at a time. Choose foods that provide key nutrients and help meet energy needs. Iron containing foods (meat, iron supplemented cereals) are required, especially for breastfed infants. Zinc intake should be encouraged with foods such as meat, dairy products, and fortified infant cereal. Phytate intake should be low to enhance mineral absorption. By 7 8 mo infants should be consuming foods from all food groups. Between 9 and 12 mo of age, encourage a cup rather than a bottle. Fluids other than breast milk, formula, and water should be discouraged. Breast milk can continue up to 24 mo of age; cows milk can be introduced at 12 mo of age and up to 24 ozday of cows milk can be consumed if breastfeeding is discontinued. Give no more than 4 ozday of 100 fruit juice; no sugar sweetened beverages. Encourage routine mealtimes and responsive feeding, watching for and responding to the childs hunger and satiety cues. Adapted from American Academy of Pediatrics. Pediatric Nutrition Handbook, 8th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2019. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. 414 Part V u Nutrition feeding may prevent IgE mediated food allergies. The most recent guidelines from the American Academy of Allergy, Asthma, and Immunology recommend early introduction of the top 9 highly aller genic foods (dairy, soy, eggs, peanuts, tree nuts, sesame, wheat, fish, and shellfish) for all children, especially those at higher risk for atopic disease. For more information, see Chapter 192. TRANSITION TO MILK Whole cows milk can be
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introduced at 12 months, and formula fed children are transitioned to milk at this time. In children 12 24 months, for whom overweight or obesity is a concern or who have a family history of obesity, dyslipidemia, or cardiovascular disease, the use of reduced fat milk may be appropriate. Otherwise, whole milk is recommended until age 24 months, after which changing to 1 milk helps reduce overall dietary intake of fat if this is a con cern. The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) does not provide 2 or whole milk for children over 24 months unless authorized by a medical provider. Regardless of the type, all animal milk consumed should be pasteur ized because of the infection risk with raw or unpasteurized milk, as discussed earlier. Nondairy alternatives to milk from plant based (e.g., soy, hemp, pea, oat, rice) and nut based (e.g., almond, cashew, peanut) sources are popular. When counseling parents, it is important to emphasize that the overall nutritional content and quality of plant based milk alternatives is not equivalent to cows milk. Although most are forti fied with vitamin A, vitamin D, and calcium, only some soy , hemp , and pea based milk alternatives have comparable protein content, and all products have inferior protein quality. Many plant based products have added oils and sugars. No nondairy alternative milks are appro priate substitutions for infant formula or breast milk in infants. Nut based milks may be suitable for toddlers 12 months of age without allergies who have an otherwise adequate diet. Nondairy (vegan) milks vary between products; a careful assessment of ingredients, including protein and micronutrient fortification, must be determined. RESPONSIVE FEEDING Responsive feeding begins in infancy and is associated with desir able growth outcomes. Responsive feeding refers to recognizing and responding to childrens signs of hunger and satiety in a timely and developmentally appropriate manner. Parents are encouraged to learn to recognize signs of hunger (e.g., child leans forward or reaches for food, or opens mouth when offered food) and satiety (e.g., child closes mouth or turns away from food) in infants who receive solid foods so that they can respond appropriately. The period from 6 months to 15 months is characterized by acquisi tion of self feeding skills as the infant learns to grasp finger foods, use a spoon, and eat soft foods (Table 61.8). Around 12 months of age, the child learns to drink from a cup, and bottle weaning around 12 15 months is recommended. To prevent dental caries, bedtime bottles should be discouraged, and it is best that cups contain only water out side of mealtimes. Sugar sweetened beverages and 100 fruit juice are not recommended for infants less than 12 months. Cups without a lid or with a straw rather than a hard spout are preferred. Baby led weaning (BLW) typically refers to allowing infants to self feed soft (often well cooked) solid or table foods from the very begin ning of complementary feeding. Presently, many
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parents are choosing to give their infants finger foods rather than, or in combination with, purees. There is little evidence that BLW leads to improved nutrient status, weight gain, or food acceptance longitudinally. In general, all food textures, including purees, are encouraged to be included in the infants diet. Parents should be counseled on avoidance of foods that are common choking hazards. FEEDING TODDLERS AND PRESCHOOL AGED CHILDREN Toddlerhood is a period when eating behaviors and healthful habits can be established, and it is often a confusing and anxiety generating period for parents. Important goals of early childhood nutrition are to offer foods that are developmentally appropriate and to begin to foster healthful eating habits that will last a lifetime. Growth after the first year slows dramatically, appetite decreases, motor activity increases, and children naturally become leaner until they reach an adiposity nadir at 4 6 years. Using growth charts to illustrate adequate growth and provide guidance about typical behavior and eating habits can help allay parents concerns if they are explained in a way that parents can understand (Table 61.9). Eating behavior can be erratic, and chil dren can appear distracted from eating as they explore the environ ment. Young children may consume a limited variety of foods, and it is common for children to like a particular food for a period and then reject the favored food. It can take many offers before children become familiar with and decide to try a novel food, and it is important to help children learn about food without expectations regarding how much they will eat. Recommended Intake and Serving Sizes Toddlers and preschool aged children usually eat three healthy meals and one to two snacks daily. Recommended daily amounts for each food group can be found in Table 61.10. Toddlers and preschool chil dren often fail to meet the recommended servings of fruits, vegetables, and fiber, whereas intakes of food with fat and added sugar are exces sive. Recommended serving sizes of fruits, vegetables, and grains are approximately the size of the childs fist, and a serving size of protein can be the size of the childs palm. It is important to be mindful that some children become overwhelmed when large portions are offered, fearing that they will be expected to finish the entire portion. If parents are concerned about their children eating enough vegetables, giving vegetables at the beginning of the meal has been shown, in some cir cumstances, to be an effective strategy for increasing vegetable con sumption in preschool children. Milk continues to be an important Table 61.8 Feeding Skills Birth to 36 Months AGE (mo) FEEDINGORAL SENSORIMOTOR SKILLS Birth to 4 6 Nipple feeding, breast or bottle Hand on bottle during feeding (2 4 mo) Maintains semiflexed posture during feeding Promotion of infant parent interaction 6 9 (transition feeding) Head and neck control Feeding more in upright position Spoon feeding thin, pureed foods Both hands to hold bottle Finger feeding of easily dissolvable solids introduced Vertical munching
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of easily dissolvable solids 9 12 Cup drinking Eats lumpy, mashed food Finger feeding for easily dissolvable solids Chewing includes rotary jaw action 12 18 Self feeding; grasps spoon with whole hand Holds cup with two hands Drinking with four to five consecutive swallows Holding and tipping bottle 18 24 Swallowing with lip closure Self feeding predominates Chewing broad range of food Up down tongue movements 24 36 Circulatory jaw rotations Chewing with lips closed One handed cup holding and open cup drinking with no spilling Using fingers to fill spoon Eating wide range of solid food Total self feeding, using fork Adapted from Arvedson JC. Swallowing and feeding in infants and young children. GI Motility Online. 2006. https:doi.org10.1038gimo17. Downloaded for mohamed ahmed (dr.mms2020gmail.com) at University of Southern California from ClinicalKey.com by Elsevier on April 20, 2024. For personal use only. No other uses without permission. Copyright 2024. Elsevier Inc. All rights reserved. Chapter 61 u Feeding Healthy Infants, Children, and Adolescents 415 source of nutrition, particularly protein, fat, calories, and vitamin D, and it is recommended that children consume up to 2 3 cups (16 24 ounces) per day (see Table 61.10). Sugar sweetened beverages like soda, sports drinks, sweetened tea, or fruit punch are not recom mended. Toddlers ages 12 months and older can be given up to 4 oz day of 100 fruit juice. Grapefruit juice can affect medications metab olized by CYP34A (e.g., antifungals such as fluconazole and ketocon azole, antiretrovirals, erythromycin, clarithromycin, fluoxetine, and amiodarone). Feeding Practices In the second year of life, self feeding is learned, becomes the norm with time, and provides more opportunities for the family to eat together. Self feeding also provides the child with the autonomy to self regulate their intake. Child feeding is an interactive process, especially because children receive cues regarding appropriate eating behaviors from par ents. Parents are encouraged to notice and comment on positive and ignore negative eating behaviors unless the behavior jeopardizes the health and safety of the child. Parents should avoid pressuring young children to eat, particularly pressuring them to eat larger, adult sized portions. Instead, parents are encouraged to focus on acceptance of a wide variety of healthful foods. In addition, parents are encouraged to eat the same foods with their toddlers to model positive eating behav iors such as trying and consuming healthful foods. The 2 year old child can progress from small pieces of soft finger foods to prepared table foods with care. They can also learn how to eat with utensils (as culturally appropriate) over the preschooler period. The young child is not capable of completely chewing and swallowing chewy or hard foods, and hard foods present a chok ing risk. Hard candies, nuts, popcorn, and raw carrots should be avoided before age 4 years. Foods like hot dogs, sausages, and grapes can be sliced lengthwise to avoid choking. Caregivers should always be vigilant and present during feeding, and the child placed in a highchair or booster seat. The AAP
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