Adrenal Disorders USMLE Step 1 Practice Question
A 33-year-old woman presents with progressive fatigue, nausea, 8-kg weight loss, and orthostatic dizziness. Vital signs show BP 98/62 mmHg, HR 102 bpm, RR 18/min, temp 36.8°C, SpO2 98%. Morning serum cortisol is 3 mcg/dL (normal >10). After cosyntropin stimulation test, cortisol rises only to 5 mcg/dL. ACTH level is elevated at 88 pg/mL. No recent medication use reported. Which diagnosis best explains these findings?
Answer choices
- APheochromocytoma
- BSIADH due to malignancy
- CCentral diabetes insipidus
- DPrimary adrenal insufficiency with impaired adrenal responseCorrect answer
- ENormal adrenal reserve
- FSecondary adrenal insufficiency with preserved adrenal responsiveness
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