Pituitary Disorders USMLE Step 1 Practice Question
A 52-year-old woman presents with progressive headaches and bitemporal hemianopsia. Vital signs show BP 128/82, HR 78, RR 16, temp 37°C, SpO2 98%. MRI reveals a 28-mm sellar mass compressing the optic chiasm. Laboratory studies demonstrate low TSH (0.1 mIU/L), low free T4 (0.6 ng/dL), normal prolactin level, and normal 24-hour urinary cortisol. She denies visual changes beyond the hemianopsia. Which of the following is the most likely diagnosis?
Answer choices
- APituitary carcinoma
- BPrimary hypothyroidism with pituitary enlargement
- CNonfunctioning pituitary adenoma with secondary hypothyroidismCorrect answer
- DTSH-secreting adenoma
- EGraves disease with pituitary hyperplasia
- FTuberculum sellae meningioma compressing the pituitary gland
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