Diabetes Mellitus USMLE Step 1 Practice Question
A 47-year-old man presents with fatigue, anorexia, and lightheadedness. He underwent resection of a nonfunctioning pituitary macroadenoma 3 months ago. Physical examination shows low blood pressure but no hyperpigmentation. Laboratory studies show low morning cortisol, low ACTH, sodium 130 mEq/L, potassium 4.2 mEq/L, and normal anion gap. Which of the following is the most likely diagnosis?
Answer choices
- ACongenital adrenal hyperplasia due to 21-hydroxylase deficiency
- BPrimary hyperaldosteronism
- CPrimary adrenal insufficiency
- DSecondary adrenal insufficiencyCorrect answer
- ETertiary hypercortisolism
- FAcute adrenal crisis due to pituitary apoplexy
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