text
stringlengths
16
2.35k
tokenCount
int64
5
450
pageStart
int64
1
43
pageEnd
int64
1
43
hash
stringlengths
64
64
Although there are no formal controlled studies of conse- quences of cure in pediatric Cushing’s syndrome, improvements in growth and body composition after treatment are reported in both patients with adrenal and those with pituitary causes (24, 25).
52
4
4
523524dff8c086d4b25f02ef65826688687f8f1951d1f7e985f85c37e0568f24
Final stature in patients with endogenous Cushing’s syn- drome was reported to be disappointing (26), but more recent data showed that most patients reach a final height within their predicted parental target range (24).
44
4
4
cd2fe6a4b5ab8c0df6d2dca449a649393ed07eddcc602d4c64383812fb996cba
Treatment of patients with moderate to severe Cushing’s syn- drome clearly reduces mortality and morbidity. Because Cush- ing’s syndrome tends to progress and severe hypercortisolism is probably associated with a worse outcome, it is likely that early recognition and treatment of mild disease would reduce the risk ofre...
90
4
4
734238c364758a94ee36a40ffff46a70adf2491fbf61312d5b725f08728103e6
OurrecommendationsfortestingforCushing’ssyndromeare based on direct evidence from observational studies indicating a large treatment effect (which we have rated as low to moderate quality evidence) on morbidity and mortality in patients diag- nosed with the condition.
56
4
4
919c6772fcb57ac5ed8d59a3b3a127350be5e9ac330abd10a31bdfa7bb971ffb
The next section of this document focuses on evidence that bears indirectly on these recommenda- tions. The research in this area yields data on the likelihood of Cushing’s syndrome in certain populations and on the accuracy of currently available tests in these populations.
52
4
4
5bd6c859a2b95030089f380ee7d12b5b7243343eb7525c81ca339aeb84a2721b
As a result, the majority of our recommendations are based on very low- to low-quality evidence. Higher-quality evidence to support testing should come from studies directly comparing the effect of testing strategies on patient-important outcomes.
45
4
4
4a0f6995e9bd8603d9b93186cbc4c01a2136e6a590fa18984aa36e643bf995b9
To date such evidence is not available in this field. These guidelines focus on the more common clinical scenar- ios, with brief mention of conditions and situations that are rare or more complicated than space limitations allow; we hope that the reader will investigate these further.
53
4
4
16f151a079033501ce6cd98d1e58bc94e65a4e6d144ba57cc456e43bc1ad5ba7
3.0 Diagnosis of Cushing’s syndrome Who should be tested 3.1Werecommendobtainingathoroughdrughistorytoexclude exogenous glucocorticoid exposure leading to iatrogenic Cush- ing’s syndrome before conducting biochemical testing (1 QQQQ ).
67
4
4
e2026bea096b86114ece2b6374c884de736148b044dcfdf41a844207b7a8818b
3.2 We recommend testing for Cushing’s syndrome in the fol- lowing groups: • Patients with unusual features for age ( e.g. osteoporosis, hypertension) (Table 1) (1 QQEE ) • Patientswithmultipleandprogressivefeatures,particularly those that are more predictive of Cushing’s syndrome (Ta- ble 1) (1 QQEE ) • Children with ...
117
4
4
3308ccfdd4504de20abf7f34b3a6e3ca44b9afdd79a675d06deb33201a8f6087
3.3 We recommend against widespread testing for Cushing’s syndrome in any other patient group (1 QEEE ). 3.1 Evidence Features of Cushing’s syndrome may occur as a result of exog- enousglucocorticoiduse.TheseverityoftheCushingoidfeatures TABLE 2.
68
4
4
481d64c3d5700eb63bfa96855ce63badabed7450ad6a8cd8c9bbc793801a93a2
Conditions associated with hypercortisolism in the absence of Cushing’s syndrome a Conditions Some clinical features of Cushing’s syndrome may be present Pregnancy Depression and other psychiatric conditions Alcohol dependence Glucocorticoid resistance Morbid obesity Poorly controlled diabetes mellitus Unlikely to have...
133
4
4
88fb6fbecba8a8bbe18496fd26cce1ad60d657c5da00249ec93a4a2d9c2e01ce
If there is a high clinical index of suspicion, the patient should undergo testing, particularly those within the first group. J Clin Endocrinol Metab, May 2008, 93(5):1526–1540 jcem.endojournals.org 1529 Downloaded from https://academic.oup.com/jcem/article/93/5/1526/2598096 by University of Wisconsin System user on 2...
93
4
4
35baa0b845171cf48ffa67d54ffcc7aaaef05cab83fbb5b4face30c7e136ea41
depends on the potency of the preparation used, its dose, the route and duration of its administration, and whether concom- itant medications prolong its half-life (27). A thorough drug his- tory noting current or recent use of these medications, oral, rec- tal, inhaled, topical, or injected, should be obtained before ...
80
5
5
3c62b165c23cd435710d8042662869ec5e09c3e3b3834254a485c2ba621730c9
In particular, glu- cocorticoid components of skin creams (including bleaching agents), herbal medications, “tonics,” and joint or nerve injec- tions may be overlooked.
44
5
5
b3ce548f258243889af0a4a18d3d58f056b948fdfc6b012038aadcffdd61bd17
Megestrol acetate (medroxyprogester- one acetate) is a synthetic progesterone derivative that has glu- cocorticoid activity and in high doses may cause Cushing’s syndrome (29).
48
5
5
78d39fb93fe5b720050ddbb90e2e193a2d090ff6a64d0b46a435c7c5b9062f9b
Our recommendation is based on high-quality evidence because it derives from the common observation that pursuing the alternative, testing to establish the diagnosis of Cushing’s syndrome without first excluding exogenous glu- cocorticoiduse,isassociatedwithaverylargeriskofundesirable effects (including unnecessary tes...
77
5
5
9f3b423223899c0d551dac869739104a80f370024127f078b3159d01cbcbcb41
3.2 Evidence Cushing’s syndrome is more likely to be present when a large number of signs and symptoms, especially those with high dis- criminatory index ( e.g. myopathy, plethora, red striae, easy bruising, and thin skin in the young) are present (6, 8).
65
5
5
186f4fb9f663fad090e42b0c1da97fd4629f14c2328ec34a0e68f271f6cc1d52
However, there is a wide spectrum of clinical manifestations at any given level of hypercortisolism. Because Cushing’s syndrome tends to progress, accumulation of new features increases the probability that the syndrome is present.
45
5
5
d38af38c5407354ffbedeaaab17123bedb99595cdbc502b37c9c5fa3524a5bc8
A review of old photographs of the patient may help the clinician better appreciate whether physical changes have occurred over time. In children, the sensitivity of combined reduced linear growth and increased weight is quite high.
40
5
5
4d6e311a2459b05fbe584859a17ef6c7ce703c9883eee6597a96ffad034af281
Although the probability of Cushing’s syndrome has not been evaluated in a large number of children, clinical experience suggests that the specificity of these clinical features for the diagnosis is also very high (30).
41
5
5
a2c87f3ead1200975f031e49c2e34b546a0778cc2e010bafdb0627b2e83b6db8
As a result, tests for Cushing’s syndrome are not indicated in obese children unless their statural growth rate has slowed. Clinicians often evaluate patients with an incidentally found adrenal nodule for autonomous adrenal cortisol excess.
47
5
5
3f6357ee8d9e7218ae61977563a8b7ed4f635f2f1b503f62c217c2144cd3ed54
Such patients usually do not present with overt clinical features of Cushing’s syndrome, but biochemical hypercortisolism is presentinalargefraction(upto10%).Bulow etal.
41
5
5
bf66073aa30c19b8214eb3f5d6c8c7645aa588925e0951f917b1a7ef74f97ef8
(31)reported 2% prevalence of Cushing’s syndrome; Libe et al. (32) reported 18%; Terzolo et al. (21) quoted 5–20%, depending on referral bias and diagnostic tests and criteria.
50
5
5
b78b46268e7c967ea47c0b31944cc22cf7c5653bbb0178ece5f3fd3609b06027
3.3 Evidence Testing for Cushing’s syndrome in certain high-risk populations has shown an unexpectedly high incidence of unrecognized Cushing’s syndrome as compared with the general population.
40
5
5
53b3d37f4b333c06ba676ace33ea8a2194cd73f55c1cf0f1514c7c2ef55d4661
Although there are limited data on the prevalence of the syn- drome in these disorders, the diagnosis should be considered. In one study, 2–3.3% of patients with poorly controlled di- abetes mellitus had surgically confirmed Cushing’s syndrome or mild hypercortisolism.
64
5
5
a224eb4d0f2b79eb7051589e631cbb15504853dc9f5583d20bfe2b5e6a720abe
Most of these patients had unilateral ad- renal adenomas (33). In another recent report, one of 99 patients with newly diagnosed diabetes mellitus had surgically proven Cushing’s disease (34).
43
5
5
af920b22bc4498414fb5597d5ec524719eda69a88408a8e25c11ae962245cf59
Another study of 86 consecutive obese subjects referred to an endocrine clinic with diabetes mellitus, hypertension, and/or the polycystic ovary syndrome found a 5.8% incidence of Cushing’s syndrome (35).
47
5
5
800e905f192fd156837e823c9f98823b6ead15a729b840ae610ebec13e73c1ca
Screening studies of patients with hypertension reported a 0.5–1% prevalence of Cushing’s syndrome (36, 37). Unsus- pected Cushing’s syndrome also was found in as many as 10.8% of older patients with osteoporosis and vertebral fracture in whom comprehensive testing was done for secondary causes (38).
75
5
5
707027750c5e056ba124f39c2f701e7fdd5ebd06e39a79a01d4a06e421c19d0e
Unfortunately, there is little information on additional co- morbidities and risk factors in these studies. The few data on the outcome, after surgical remission of hy- percortisolism, in patients with unsuspected Cushing’s syn- drome are mixed; hypertension and diabetes did not improve in all individuals (20–23).
69
5
5
593a46c39a3c252c98032aa8982355a3fb9c4ad0a75df2c3b30f34bf55cfd0e5
Patients with familial disease that puts them at risk of Cush- ing’s syndrome ( e.g. Carney complex, multiple endocrine neo- plasia-1) should be evaluated by an endocrinologist as part of a surveillance screening program.
53
5
5
81af0342f5dea76979b60af9e1dfca793b990da123ecb43873ef64a7701876e2
3.3 Values Because of the rarity of Cushing’s syndrome, the high prevalence of conditions such as diabetes mellitus, obesity, and depression, andthelimitationsofthescreeningtests,theriskoffalse-positive test results is high.
53
5
5
6cf202d51f0f041082ebf8461aa15333ad0a3536fbabb713139a0b6ebee5057e
False-positive results, with their attendant costs, are reduced if case detection is limited to individuals with an increased pretest probability of having the disorder. The sub- sequent testing, labeling, and treatment may harm individuals with false-positive results and distract attention from the treat- ment of the ...
64
5
5
e1d5a0073ce6807fce241ae4dee1541580bd5799e246c119f906d07bf65a5d0d
The proposed testing strategy places higher value on reducing the number of false-positive test results, particularly in patients with very mild disease in whom the benefits of intervention are unproven. Conversely, once the clinical scenario suggests a high pretest probability of the disorder, sensitivity needs to be ...
63
5
5
c5f4c3bf1a042c1541aa1f2e893118a484468bbc5af410cc4d720034e66b9c76
This approach also seeks to use more convenient and less expensive tests. Initial testing 3.4 For the initial testing for Cushing’s syndrome, we recom- mendoneofthefollowingtestsbasedonitssuitabilityforagiven patient (Fig.
54
5
5
f027f41a87e8df8bf51e4781c347a45d4a598cc66fd15cd9997b34d0c06c7625
1) (1 QEEE ): 3.4.1 UFC (at least two measurements) 3.4.2 Late-night salivary cortisol (two measurements) 3.4.3 1-mg overnight DST 3.4.4 Longer low-dose DST (2 mg/d for 48 h) 3.5 We recommend against the use of the following to test for Cushing’s syndrome (1 QEEE ):
92
5
5
856b8e249178cd3af80b2bd507a8cbe0997c1b04db87c81b96e1b5a135db14dd
• Random serum cortisol or plasma ACTH levels • Urinary 17-ketosteroids • Insulin tolerance test • Loperamide test • Tests designed to determine the cause of Cushing’s syn- drome ( e.g.
49
5
5
9d7147562abaa28ae9ff580301b9bda686fddaa22feffe8e270dcd063a52941a
pituitary and adrenal imaging, 8 mg DST). 3.6 In individuals with normal test results in whom the pretest probability is high (patients with clinical features suggestive of 1530 Nieman et al.
45
5
5
b42f90b86387d1142995feb9fd36292f6bd69010482d93676a2195a571d12182
Guidelines for the Diagnosis of Cushing’s Syndrome J Clin Endocrinol Metab, May 2008, 93(5):1526–1540 Downloaded from https://academic.oup.com/jcem/article/93/5/1526/2598096 by University of Wisconsin System user on 20 February 2026
72
5
5
ff1fcbc856e62ff8dac438999f1d14b8790e11a636ff529706340a4bfea48f83
Cushing’s syndrome and adrenal incidentaloma or suspected cy- clic hypercortisolism), we recommend further evaluation by an endocrinologist to confirm or exclude the diagnosis (1 QEEE ).
43
6
6
01c776a8be4d2c631f34ddba25cda60af7ec5f200fcf48ad09b5d0f46b965e5b
3.7 In other individuals with normal test results (in whom Cush- ing’s syndrome is very unlikely), we suggest reevaluation in 6 months if signs or symptoms progress (2 QEEE ).
43
6
6
ece5bd5a3ac0db1628f4e6cbfc46280a200c133a96187d18fb646d514c492322
3.8 In individuals with at least one abnormal test result (for whom the results could be falsely positive or indicate Cushing’s syndrome), we recommend further evaluation by an endocrinol- ogist to confirm or exclude the diagnosis (1 QEEE ).
54
6
6
ffacfe937602f035dd98711f31be335935641dd22a2b5a7566a9a8bb648c9ed2
3.4 Evidence In this section, we first discuss the testing strategies and then provide evidence for and remarks about each of the recom- mended tests that can be used to identify patients with Cushing’s syndrome.
46
6
6
39bcf5cb2dc87db674d82e7a17211f9cfee7b5c9cfba78ded88ee324ca525cd9
Nonendocrinologist clinicians may perform the initial eval- uation for Cushing’s syndrome (or refer to an endocrinologist). In this setting, the goal is to choose a test with a high sensitivity for the disorder; unfortunately, no test has optimally high spec- ificity, so that false-positive results may occur.
70
6
6
1d513890bd7d6c1a7e357d2319cad810f57be7c5705f155ee9350744cd05d03a
The four recom- mended tests have acceptable diagnostic accuracy when the sug- gested cutoff points are used (2, 30). If the initial testing results arenormal,assumingthatthereisnoreasontomistrusttheresult (see remarks below), then the patient is very unlikely to have Cushing’s syndrome.
70
6
6
060a18d864c8003a323e90896ba56967750d13195398b7a0b3a167d7159fef62
Thus, the patient can be reassured and no further testing need be done; a recommen- dation to return in 6 months if symptoms progress ensures that evolving symptoms or new features will not be ignored.
41
6
6
7b6a1732a951340f4e343de4cfde20a9bb1d8966f24a65ae3cb6ef649d7d0868
Inpatientswithahighpretestprobability of Cushing’s syndrome, to expedite diagno- sis, the physician may elect to perform two tests simultaneously. 3.4 Remarks for all tests Measurement of cortisol (urine, serum, or salivary) is the end point for each of the rec- ommended tests.
77
6
6
ce0473c20cfe8c1312a8631b960f1b606434ddc4aa024706a31df9cc188f9ae7
As with all hormone as- says, the physician must be aware that sev- eral collection and assay methods are available for the measurement of cortisol, and results for a single sample measured in various assays may be quite different (39).
49
6
6
aab9a29d90c29d16afe7c17d396adc4df0f084267692ee745dc543854c143866
Assays differ widely in their accuracy; re- sults near the cutoff value on a single mea- surement often can be explained by assay variability. In particular, the expected sali- vary and serum concentrations in these tests are close to the functional limit of detection of the assays.
60
6
6
a713fac5f44bc3f3ab6a453908fbcf36265459cce251e897757b7faa58140d69
Because precision deteriorates at these levels, assays should be chosen on the basis of their performance at this low range. Normal ranges vary substantially, de- pendingonthemethodused,soitisessential to interpret test results in the context of the appropriate normal range.
53
6
6
a3edf23cf47d25aa78b20cc13677e6f2b41cb7b94915744a07f3eda11c081a82
Antibody-based immunoassays such asunextractedRIAandELISAcanbeaffectedbycross-reactivity with cortisol metabolites and synthetic glucocorticoids. In con- trast, structurally based assays such as HPLC and tandem mass spectrometry (LC-MS/MS) do not pose this problem and are being used with increasing frequency.
79
6
6
a16088cc36eb62a32589756259325e99c909875da3bde9e512741e982eb7942a
However, there are also drugs (carbamazepine and fenofibrate) that may interfere with someofthesechromatographicmethods(Table3),therebycaus- ing falsely elevated values (40, 41).
49
6
6
20ddfb20ccdba73ac4f362dd41714fcc19ba8a3772cf7e9116fd05c9206a2eb9
Upper limits of normal are much lower with HPLC or LC-MS/MS than in antibody-based assays. For example, urine cortisol values obtained using HPLC may be as low as 40% of the value measured by RIA (42, 43).
54
6
6
f8a166277688dcedd747d349c4070b3114d118d13ccd2b0790434b0a2e304414
Estrogens increase the cortisol-binding globulin (CBG) con- centration in the circulation. Because serum assays measure total cortisol, false-positive rates for the overnight DST are seen in 50% of women taking the oral contraceptive pill (44).
53
6
6
b120871a05b498f6eadf5e5b58f2f59eed01df8d47cb930eb9137b8c5879f44f
Wherever possible, estrogen-containing drugs should be withdrawn for 6 wkbeforetestingorretesting(45).Conversely,decreasesinCBG or albumin, which occur in the critically ill or nephrotic patient, are associated with decreased serum cortisol values (39, 46).
61
6
6
99abfb8f3de4b99082ed47a3afeab95e168c6e18c341c9191dcb182efec132b3
Because the hypercortisolism of Cushing’s syndrome can be variable, we recommend that at least two measurements of urine or salivary cortisol be obtained. This strategy increases confi- denceinthetestresultsifconsistentlynormalorabnormalresults are obtained.
59
6
6
8f75149c9c1dcbc93de130294d1b2ba6e2abc4ae1f96ef0411138b151308f728
Cushing’s syndrome suspected Perform one of the following tests ANY ABNORMAL RESULT Normal (CS unlikely) Consult endocrinologist Discrepant (Suggest additional evaluation) Normal (CS unlikely) ABNORMAL Cushing’s syndrome Exclude exogenous glucocorticoid exposure (consider endocrinologist consultation) 24-h UFC (> 2 tes...
166
6
6
4dd61817a3e51aba08dc1313b4c02f5a41a016ed75a2e8787b2fe8983178b219
Algorithm for testing patients suspected of having Cushing’s syndrome (CS). All statements are recommendations except for those prefaced by suggest. Diagnostic criteria that suggest Cushing’s syndrome are UFC greater than the normal range for the assay, serum cortisol greater than 1.8  g/dl (50 nmol/liter) after 1 mg ...
106
6
6
72473c186c8b76207b1097b4b296a306d50281bb9b3d5f8bacbf7f1f48fdecc2
J Clin Endocrinol Metab, May 2008, 93(5):1526–1540 jcem.endojournals.org 1531 Downloaded from https://academic.oup.com/jcem/article/93/5/1526/2598096 by University of Wisconsin System user on 20 February 2026
70
6
6
bfff484a1b7e37b4915c41b57740b40a60fe87d93e65ef471a34ef831bce0f89
Remarks for dexamethasone tests Variable absorption and metabolism of dexamethasone may in- fluence the result of both the overnight 1-mg DST and the 48-h, 2 mg/d test.
47
7
7
c1340552f8ad7ba4f99bfe40c45e88f494c64a304da560145222283b7215a54c
Drugs such as phenytoin, phenobarbitone, carbam- azepine, rifampicin, and alcohol induce hepatic enzymatic clear- ance of dexamethasone, mediated through CYP 3A4, thereby reducing the plasma dexamethasone concentrations (Table 3) (47).
71
7
7
76291247c665752126ee13f68155ce21e76acae36ef533b905c92b65ee8ffcc6
Conversely, dexamethasone clearance may be reduced in patients with liver and/or renal failure. Dexamethasone levels show interindividual variation, however, even in healthy indi- viduals on no medication.
49
7
7
974cc15d1da922a3ee52aa3acb85055d691862843ae32bf8d2d60aa62d941134
To evaluate for false-positive and negative responses, some experts have advocated simultaneous measurement of both cor- tisol and dexamethasone for these tests to ensure adequate plasma dexamethasone concentrations [  5.6 nmol/liter (0.22  g/dl)] (48).
64
7
7
2720a3f14e4971158b53426574850af3332df18bddd61ec2a403699092ec0869
However, given the limited availability outside the United States and cost of the dexamethasone assay, this other- wise desirable approach may not be feasible. As noted above, false-positive rates for the overnight DST are seen in 50% of women taking the oral contraceptive pill because of increased CBG levels (44).
66
7
7
e67de3dc799097f140beb7b81c9129eec8587fd61029df0ded00b2a2f524dd68
3.4.1 Evidence for use of UFC The introduction of UFC represented a major advance over mea- surement of 17-hydroxycorticosteroids (17OHCS), which re- flects both urine metabolites and cortisol.
51
7
7
0e6548648cfdb423f3d660ac43aa8af621b8a72e1bd77decf27edf46182bf894
Because 17OHCS has high rates of false-positive and negative results, it is now rarely used. Since the 1970s, experts have advocated the use of UFC for making the diagnosis of Cushing’s syndrome (49, 50).
49
7
7
a1972389ee1ec7c9055dee059c56041dd0d5f73a1469625cdf7cebd0ecc1eb54
UFC pro- vides an integrated assessment of cortisol secretion over a 24-h period. It measures the cortisol that is not bound to CBG, which is filtered by the kidney unchanged. Therefore, unlike serum cortisol, which measures both CBG-bound and free hormone, UFC is not affected by conditions and medications that alter C...
68
7
7
89e61a57418a8cf94f99979ccd48309a8fb12325c5c301b13be8aef7c3279a4b
For example, healthy women taking oral estrogen may have increased CBG, and therefore high serum cortisol concen- tration, but their UFC remains normal. Because cortisol produc- tion is increased in Cushing’s syndrome, the amount of unbound hormone is higher, resulting in elevated UFC values.
62
7
7
a323b2c805ca99728540ceac73012f9f27af192d2b2bd864d8f8a900eef3b51b
As with any other test, sensitivity and specificity of UFC are subject to the cutoffs selected. When the assay upper limit of normal is used as a criterion, the overall evidence supports the diagnostic accuracy of UFC in adults suspected of having Cush- ing’s syndrome (2, 51).
59
7
7
7747e212ccc0adc57bc91241abdd93e50cf1b7c2ae748f8f3b089c99c82f199f
Sensitivity for Cushing’s syndrome in pediatric patients is high (  89%) (30). Thus, to achieve the goal of high sensitivity, we recommend using the upper limit of normal for the particular assay as the criterion for a positive test, provided the creatinine shows that the collection is complete and there is not excess...
70
7
7
700751d55d8f7d3f88a81cde6057546ef449b2bd4a69be3e99ad6b8784eadeed
For pediatric patients, the adult normal ranges may be used because most pediatric patients are of adult weight ( i.e.  45 kg). At the recommended cutoff point, false-positive elevations of UFC may be seen in several conditions.
49
7
7
d789ad0a7a393d01fddba55018b17ceaca56bef657df23383102ee77b9a0fde2
High fluid intake (  5 liters/d) significantly increases UFC (52). Any physiological or pathological condition that increases cortisol production raises UFC (Table 2). Therefore, in these conditions a normal result is more reliable than an abnormal one. At the recommended cutoff point, false-negative results of urine ...
67
7
7
5d6f8bab5f79ee976359a3d53947f3305fcf30c4c1fde7cc69b2941549c4a098
Because UFC reflects renal filtration, values are significantly lower in patients with moderate to severe renal impairment. A falsely low UFC can occur when creatinine clearance falls less than 60 ml/min, and UFC levels fall linearly with more severe renal failure (53).
54
7
7
da68c36f39488f744e6a8941643bdcc74410a2525ee43bead9d2a75b2e87c485
UFC can be normal if a patient has cyclic disease and collects urine when the disease is inactive. Finally, it may be normal in some patients with mild Cushing’s syndrome, in whom salivary cor- tisol may be more useful (54).
54
7
7
8425a23e644ede87c2e279dc7c7e8797070035178db9b0cd346e1663c6363ca6
3.4.1 Remarks for UFC Sample collection and instructions It is important to ensure that patients provide a complete 24-h urine collection with appropriate total volume and urinary cre- atininelevels.Thismayrequirepatienteducationusingbothoral and written instructions.
54
7
7
ec3bf175b376c971e627e5043452d7056676d26d1efcc669070627d77ed82418
The first morning void is discarded so that the collection begins with an empty bladder. All subsequent voids throughout the day and night should be included in the collection, which is kept refrigerated (but not frozen), up to and including the first morning void on the second day.
55
7
7
671ded7d362cccd2f776891eabdab41c7536c5354243425015c28eda878cf05c
Once the bladderhasbeenemptiedintothecollectiononthesecondmorn- ing, the sample is complete. Patients should be instructed not to drink excessive amounts of fluid and to avoid the use of any glucocorticoid preparations, including steroid-containing skin or hemorrhoid creams, during TABLE 3.
63
7
7
2698d4c9000b1bf8edef731365fd90470c0b77ef64af8352b7a4c05513cd549f
Selected drugs that may interfere with the evaluation of tests for the diagnosis of Cushing’s syndrome a Drugs Drugs that accelerate dexamethasone metabolism by induction of CYP 3A4 Phenobarbital Phenytoin Carbamazepine Primidone Rifampin Rifapentine Ethosuximide Pioglitazone Drugs that impair dexamethasone metabolism ...
212
7
7
6dab7a3a17e95475eb694766365a2b7f0c6f26114e4a30eff3f4f1915610a0fe
Data regarding CYP3A4 obtained from http://medicine.iupui.edu/flockhart/table.htm. 1532 Nieman et al. Guidelines for the Diagnosis of Cushing’s Syndrome J Clin Endocrinol Metab, May 2008, 93(5):1526–1540 Downloaded from https://academic.oup.com/jcem/article/93/5/1526/2598096 by University of Wisconsin System user on 20...
107
7
7
9f7974e4a0f883fce4bac0acd414951374bf407f368b22f7f9c2a46ef53e1f4c
the collection. Because UFC levels in a patient with Cushing’s syndrome are variable, at least two collections should be per- formed, particularly in children in whom reproducibility can be low.
41
8
8
52292ce31ef8f83ca01917ac2f403cc950d7f0233eda8a34b643993de825770c
3.4.2 Evidence for late-night salivary cortisol In healthy individuals with stable conventional sleep-wake cy- cles, the level of serum cortisol begins to rise at 0300–0400 h, reaches a peak at 0700–0900 h, and then falls for the rest of the day to very low levels when the person is unstressed and asleep at midnight (5...
81
8
8
fa599e21d7905c20337feb7f22f961278b5254d3a01f8897830f2006d4c07ef9
The loss of circadian rhythm with absence of a late-night cortisol nadir is a consistent biochemical abnormality in patients with Cushing’s syndrome (56, 57). This difference in physiology forms the basis for measurement of a midnight serum or late-night salivary cortisol.
58
8
8
e4206156b5a81c1095f365852b1f777efe1bdaa898b1b3c0600c6ef2b81d5585
Biologically active free cortisol in the blood is in equilibrium with cortisol in the saliva, and the concentration of salivary cor- tisol does not appear to be affected by the rate of saliva produc- tion.
44
8
8
7bcad8288a179ba51c08b1a655c575fb7f73b1bb9bd47f2e4e3d9b5f892d2405
Furthermore, an increase in blood cortisol is reflected by a change in the salivary cortisol concentration within a few min- utes (58). Various methods have been used to measure cortisol in the saliva, resulting in different reference ranges and yielding differences in sensitivity and specificity (59–67).
58
8
8
c68349eae98651cb823e30aee83d7566d17aabcde820320a9360ec22ee7f8389
The best-vali- datedassaysusedintheUnitedStatestomeasuresalivarycortisol are an ELISA and an assay performed by LC-MS/MS (28).
40
8
8
db1fd842253354fdae4069106f24458c6ec7e29931a36fbfca59a891b279fe82
When these two assay techniques are used, normal subjects usually have salivary cortisol levels at bedtime, or between 2300 and 2400 h, of less than 145 ng/dl (4 nmol/liter).
43
8
8
89c89082655f0e2aabec96367fa0ae0f66315b050b60b9376d499ebaece68e22
Using a variety of assays and diagnostic criteria, investigators from different coun- tries have reported that late-night salivary cortisol levels yield a 92–100%sensitivityanda93–100%specificityforthediagnosis of Cushing’s syndrome (59–67).
59
8
8
a633dda3a457387037c937d4577cb8a61720a70b1801a11705e059c7742ab323
Overall, the evidence in adults suggeststhattheaccuracyofthistestissimilartothatofUFC(2). This easily performed, noninvasive test has been used in children to differentiate patients with Cushing’s syndrome from those with simple obesity.
55
8
8
137616628d01a7a991707697833fd5fc751cdf59f5fc1a297d9feebf48c10a21
Investigators have reported high sensitivity (100%) and specificity (95.2%) for Cushing’s syndrome in this setting (68). The influence of gender, age, and coexisting medical condi- tions on the late-night salivary cortisol concentrations has not beenfullycharacterized.Itisimportanttonotethatthecircadian rhythm is blunt...
102
8
8
154803a802b5aad2a103553985820bec20d7fb6321b0f4270a6d81f6fb343745
Other populations may have a high percentage of false-positive results. For example, in a study of men aged 60 yr or older, Liu et al. (72) reported that 20% of all participants and 40% of diabetichypertensivesubjectshadatleastoneelevatedlate-night salivary cortisol measurement.
72
8
8
9bfaec46baa80a38b5f31b43aaa143ccc996e6bcebc72f72cb887604d4edca5a
Using the upper reference range of each assay as the cutoff point, Baid et al. (28) measured bed- time salivary cortisol levels in a large number of obese subjects and found a specificity of only 85% when they used a RIA tech- nique, but a better specificity of 92% when tandem mass spec- trometry was used.
74
8
8
1bc5ca56ff690422ad6a5b9ae6b7f00ec85e214ed6a9ad729605283677f974fc
3.4.2 Remarks for late-night salivary cortisol Most clinicians using the late-night salivary cortisol test ask pa- tientstocollectasalivasampleontwoseparateeveningsbetween 2300 and 2400 h.
53
8
8
9382ee79666f7e358d784977531b9110cee9450faf17fccc9563452e95a3d11a
Saliva is collected either by passive drooling into a plastic tube or by placing a cotton pledget (salivette) in the mouth and chewing for 1–2 min. The sample is stable at room or refrigerator temperature for several weeks and can be mailed to a reference laboratory.
58
8
8
9e3323f6c87832cef5611903d0ea955151885084e1b8ece88eec2259ee10d1f7
Reports show good correlation between salivary and simultaneous serum cortisol values in healthy vol- unteers(73,74).Whensampleswereobtainedatthesamesitting, those collected using the salivette device had lower cortisol con- centrations than those collected from passive drooling, but they correlated better with total a...
73
8
8
1df8a1c77e9f4ff6b975a2372006de76614661d671078ffd814ce1b8fc71631f
Several factors that affect the salivary cortisol test should be considered when evaluating the results. The salivary glands ex- press 11  -hydroxysteroid dehydrogenase type 2 (11  -HSD2), which converts the biologically active cortisol to inactive corti- sone (75).
64
8
8
72d9b6820f7a1aae15e5fcd1753b4e90acaab829dead213f62fe036f96f7c61e
It is theoretically possible that individuals using lico- rice or chewing tobacco (both of which contain the 11  -hydrox- ysteroid dehydrogenase type 2 inhibitor glycyrrhizic acid) may have a falsely elevated late-night salivary cortisol.
57
8
8
aa13f0504c18767b09fc013d92c2391b4b9a338276fcae439efcc3f5e0f2c130
Patients who smoke cigarettes also have been shown to have higher late-night salivary cortisol measurements than do nonsmokers (76). Al- though the duration of this effect is not known, it seems prudent to avoid cigarette smoking on the day of collection.
53
8
8
58af8e6cb6fcedb8e10af038240ebb5b7b322b93e31d77a10097641f612e9e0a
Direct con- tamination of the salivette by steroid-containing lotion or oral gels also may result in false-positive results. Because the test assumes a nadir of cortisol in the late evening, it may not be appropriate for shift workers or those with variable bedtimes, and the timing of the collection should be adjusted ...
87
8
8
c0d70350c58e9c158816cdec631e25c38d57beea40c9d248579077b9e57693d2
Similarly, nocturnal salivary cortisols may be transiently abnor- mal in individuals crossing widely different time zones. Finally, stress immediately before the collection also may increase sali- vary cortisol physiologically; therefore, ideally, samples should be collected on a quiet evening at home (64).
62
8
8
984695e12961f03d4256ed4b9c0f4148481382af50a70986a1a3b8819a9c9f9c
Theoretically, contamination with blood might increase sal- ivary cortisol levels. Although Kivlighan et al. (77) reported that minor to moderate blood leakage as a result of vigorous tooth brushing had no effect on salivary cortisol values, the possible effect of gingivitis or oral sores or injury is not known.
70
8
8
16de53d9cf3aa0bc4e9029a7b6bf467da0bba13ee31f5006fb407df2aa028bae
3.4.3 Evidence for the 1-mg DST In normal subjects, the administration of a supraphysiological dose of glucocorticoid results in suppression of ACTH and cor- tisol secretion.
45
8
8
bb2446a44c618172787d0d414eba9b07a40adf90082f511564b36da24d767f75