Pituitary Disorders USMLE Step 1 Practice Question
A 67-year-old man with severe hypertension (BP 178/104 mmHg) and hypokalemia (K+ 2.8 mEq/L) undergoes evaluation. Morning cortisol is 42 mcg/dL (normal <20), ACTH is 8 pg/mL (normal 10-50), and aldosterone is elevated at 28 ng/dL with suppressed plasma renin. Low-dose dexamethasone suppression test does not suppress cortisol. Which of the following is the most likely diagnosis?
Answer choices
- AEctopic ACTH syndrome
- BPrimary hyperaldosteronism
- CGlucocorticoid remediable hypertension
- DPituitary ACTH-secreting adenoma
- EAdrenocortical carcinomaCorrect answer
- FAdrenal adenoma with autonomous cortisol secretion
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