{ "schema_version": "1.0", "level": "genus", "genus": "Acinetobacter", "overview": { "short": "Acinetobacter species are Gram-negative, strictly aerobic, non-fermentative coccobacilli widely distributed in the environment.", "clinical_context": "Clinically significant species, particularly Acinetobacter baumannii, are important causes of healthcare-associated infections." }, "expected_fields": { "Gram Stain": "Negative", "Shape": "Coccobacilli", "Motility": "Negative", "Capsule": "Variable", "Spore Formation": "Negative", "Haemolysis": "Negative", "Haemolysis Type": "None", "Media Grown On": [ "Blood Agar", "MacConkey Agar" ], "Colony Morphology": [ "Smooth", "Opaque", "Grey-White" ], "Oxygen Requirement": "Aerobic", "Growth Temperature": "20//44", "Catalase": "Positive", "Oxidase": "Negative", "Indole": "Negative", "Urease": "Variable", "Citrate": "Variable", "Methyl Red": "Negative", "VP": "Negative", "H2S": "Negative", "DNase": "Variable", "ONPG": "Negative", "Coagulase": "Negative", "Gelatin Hydrolysis": "Variable", "Esculin Hydrolysis": "Negative", "Nitrate Reduction": "Negative", "NaCl Tolerant (>=6%)": "Variable", "Lipase Test": "Variable", "Lysine Decarboxylase": "Negative", "Ornithine Decarboxylase": "Negative", "Ornitihine Decarboxylase": "Negative", "Arginine dihydrolase": "Negative", "Glucose Fermentation": "Negative", "Lactose Fermentation": "Negative", "Sucrose Fermentation": "Negative", "Maltose Fermentation": "Negative", "Mannitol Fermentation": "Variable", "Sorbitol Fermentation": "Negative", "Xylose Fermentation": "Negative", "Rhamnose Fermentation": "Negative", "Arabinose Fermentation": "Negative", "Raffinose Fermentation": "Negative", "Trehalose Fermentation": "Negative", "Inositol Fermentation": "Negative", "Gas Production": "Negative", "TSI Pattern": "K/K", "Colony Pattern": "Unknown", "Pigment": "None", "Motility Type": "None" }, "field_notes": { "Motility": "Acinetobacter species are characteristically non-motile.", "Oxidase": "Oxidase negativity is a key differentiator from many other non-fermenters.", "Shape": "Often appear as plump coccobacilli on Gram stain." }, "key_differentiators": [ { "field": "Oxidase", "expected": "Negative", "distinguishes_from": ["Pseudomonas", "Burkholderia"], "notes": "Oxidase negativity is critical in separating Acinetobacter from most non-fermenters." }, { "field": "Motility", "expected": "Negative", "distinguishes_from": ["Stenotrophomonas", "Alcaligenes"], "notes": "Non-motility supports Acinetobacter." }, { "field": "Glucose Fermentation", "expected": "Negative", "distinguishes_from": ["Enterobacterales"], "notes": "Non-fermentative metabolism excludes Enterobacterales." } ], "common_confusions": [ { "genus": "Pseudomonas", "reason": "Shared non-fermentative metabolism but differs by oxidase status." }, { "genus": "Stenotrophomonas", "reason": "Overlapping non-fermentative profile with variable biochemical reactions." } ], "when_to_question_identification": [ "Oxidase positivity argues against Acinetobacter.", "Motility suggests an alternative non-fermenter.", "Anaerobic growth is inconsistent." ], "recommended_next_tests": [ { "test": "Oxidase test", "reason": "Primary discriminator among non-fermenters." }, { "test": "MALDI-TOF MS", "reason": "Reliable genus- and species-level identification." }, { "test": "Antimicrobial susceptibility testing", "reason": "Clinically important due to frequent multidrug resistance." } ], "supported_species": [ "baumannii", "calcoaceticus", "lwoffii", "johnsonii", "pittii" ] }