Diabetes Mellitus USMLE Step 1 Practice Question
A 35-year-old woman presents with a 3-month history of chronic fatigue, progressive weight loss, and orthostatic dizziness. She reports intense salt cravings. Vital signs show BP 95/60 mmHg, HR 102 bpm, RR 18/min, temperature 37.2°C. Physical examination reveals diffuse hyperpigmentation of the buccal mucosa and oral mucous membranes. Laboratory studies show sodium 128 mEq/L, potassium 5.8 mEq/L, cortisol 2 mcg/dL, and ACTH 145 pg/mL. No fever or focal infection is noted. Which of the following is the most likely diagnosis?
Answer choices
- AAddison diseaseCorrect answer
- BPheochromocytoma
- CSecondary adrenal insufficiency
- DCushing disease
- EConn syndrome
- FAcute adrenal crisis due to meningococcal sepsis
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