A low-dose dexamethasone suppression test is performed on a 48-year-old woman with severe depression accompanied by delusions of poverty and guilt. Cortisol fails to suppress the following morning. This result is most consistent with which subtype of depression?
- A Atypical depression
- B Melancholic depression with psychotic features ✓
- C Persistent depressive disorder
- D Premenstrual dysphoric disorder
Correct answer: B. Melancholic depression with psychotic features
Explanation
Nonsuppression of cortisol after dexamethasone reflects hyperactivity of the hypothalamic-pituitary-adrenal axis, classically seen in melancholic and psychotic depression. Psychotic depression shows among the highest nonsuppression rates, consistent with hypercortisolemia. Atypical depression tends to show enhanced rather than reduced suppression, and persistent depressive disorder and PMDD are not associated with reliable nonsuppression. The test is no longer used diagnostically but remains a classic examination link between HPA axis biology and depression subtypes.
Reference: Kaplan and Sadock's Synopsis of Psychiatry, 12th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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