Adrenal Disorders USMLE Step 1 Practice Question
A 45-year-old woman presents with progressive proximal muscle weakness, purple striae, central obesity, and hypertension. Laboratory studies show elevated 24-hour urinary free cortisol and a plasma cortisol of 8 μg/dL at 8 AM. The low-dose dexamethasone suppression test shows cortisol of 18 μg/dL. Which of the following is the most likely diagnosis?
Answer choices
- AAdrenal insufficiency
- BPrimary hyperaldosteronism
- CCushing syndromeCorrect answer
- DThyroiditis
- EPheochromocytoma
- FFamilial glucocorticoid deficiency
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