Adrenal Disorders USMLE Step 1 Practice Question
A 35-year-old woman presents with progressive fatigue, weakness, and diffuse skin hyperpigmentation. Vital signs show hypotension (90/55 mmHg), heart rate 102 bpm, and temperature 37.2°C. Laboratory studies reveal hyponatremia (128 mEq/L), hyperkalemia (5.8 mEq/L), elevated morning plasma ACTH (150 pg/mL), and low morning cortisol (3 μg/dL). She denies recent illness or fever. She takes no medications. Which of the following is the most likely diagnosis?
Answer choices
- ACushing syndrome
- BPrimary adrenal insufficiency (Addison disease)Correct answer
- CSecondary adrenal insufficiency from pituitary adenoma
- DHyperaldosteronism with secondary hypokalemia
- EAcute adrenal crisis from sepsis
- FCongenital adrenal hyperplasia with 11β-hydroxylase deficiency
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