Cushing's syndrome presenting as obesity — SCE Endocrinology MCQ

Correct answer: E — A second validated cortisol test before aetiological imaging

The best answer is “A second validated cortisol test before aetiological imaging”. Discriminating catabolic signs and failed suppression create a high pre-test probability, but endogenous Cushing syndrome should be confirmed with repeat dexamethasone, late-night salivary cortisol or urinary free cortisol before ACTH-directed localisation. “Treat presumed simple obesity before completing endocrine assessment” is less appropriate because the physical phenotype and abnormal screening result require focused endocrine evaluation “Proceed directly to pituitary surgery from the physical signs” is less appropriate because no pituitary source has been established and biochemical confirmation precedes invasive treatment “Order adrenal CT as the first confirmation test” is less appropriate because imaging before biochemical confirmation creates incidentaloma-driven misdiagnosis “Start levothyroxine as treatment for weight gain” is less appropriate because thyroid hormone is not an obesity drug and has no indication from the stated data

Reference: Consensus on diagnosis and management of Cushing disease. https://pmc.ncbi.nlm.nih.gov/articles/PMC8743006/