Pituitary Disorders USMLE Step 1 Practice Question
A 52-year-old man who underwent pituitary adenectomy 2 years ago presents with progressive fatigue and confusion. Vital signs show BP 92/58 mmHg, HR 88 bpm, RR 16, temp 36.8°C. Serum sodium is 126 mEq/L, free T4 is 0.6 ng/dL (low), and TSH is 1.2 mIU/L (normal). Morning cortisol is not measured. He denies recent head trauma or medications. Which diagnosis best explains this clinical presentation?
Answer choices
- APrimary hypothyroidism
- BCentral hypothyroidismCorrect answer
- CSecondary adrenal insufficiency
- DAutoimmune adrenalitis
- EThyroiditis with transient hyperthyroidism
- FPsychogenic hyponatremia
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