Pituitary Disorders USMLE Step 1 Practice Question
A 28-year-old man presents with tall stature, long limbs, and gynecomastia. Vital signs show BP 118/76, HR 72, RR 16, temp 37°C. Physical examination reveals small firm testes and sparse facial hair. Laboratory studies demonstrate elevated FSH (18 mIU/mL) and LH (15 mIU/mL), low testosterone (2.1 ng/dL), and elevated prolactin (28 ng/mL). Pituitary MRI shows normal anatomy. No galactorrhea is noted. Which diagnosis best explains these findings?
Answer choices
- AKlinefelter syndrome with mild hyperprolactinemiaCorrect answer
- BHemochromatosis with iron deposition in testes
- CProlactinoma causing testicular failure
- DCentral hypogonadism from GnRH deficiency
- EPituitary adenoma with stalk effect
- FAndrogen insensitivity syndrome with secondary hypogonadotropic hypogonadism
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