Pituitary Disorders USMLE Step 1 Practice Question
A 38-year-old man with prior transsphenoidal pituitary surgery presents with progressive fatigue, weight gain, and hypotension. Vital signs show BP 92/58 mmHg, HR 72/min, RR 16/min, temperature 36.8°C. Laboratory studies reveal cortisol 3 μg/dL, ACTH 45 pg/mL, free T4 0.6 ng/dL with TSH 1.2 mIU/L, and normal prolactin. He denies headaches or visual changes. Which of the following best explains these findings?
Answer choices
- ASecondary adrenal insufficiencyCorrect answer
- BCentral hypothyroidism
- CPrimary hypothyroidism
- DGraves disease
- EPrimary adrenal insufficiency
- FHypopituitarism with selective preservation of gonadotropin-releasing hormone
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