Adrenal Disorders USMLE Step 1 Practice Question
A 28-year-old man presents with progressive fatigue, weakness, and weight loss over 3 months. On examination, he has diffuse hyperpigmentation and appears cachectic. Vital signs: BP 98/62 mmHg, HR 102 bpm, RR 18/min, Temp 37.2°C. Labs reveal Na+ 128 mEq/L, K+ 5.8 mEq/L, cortisol 3 µg/dL at 8 AM (normal 10-20), and ACTH markedly elevated at 156 pg/mL. No recent medication use or abdominal pain reported. Which is the most likely diagnosis?
Answer choices
- ACongenital adrenal hyperplasia
- BAcute adrenal hemorrhage
- CCushing syndrome
- DAddison diseaseCorrect answer
- ESecondary adrenal insufficiency
- FAdrenocorticotropic hormone-secreting pituitary adenoma
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