Calcium and Parathyroid USMLE Step 1 Practice Question
A 45-year-old man with newly diagnosed hypertension presents with progressive muscle weakness and fatigue. Vital signs show BP 158/94 mmHg, HR 88/min, RR 14/min, temp 37°C, SpO2 98% on room air. Laboratory studies reveal serum calcium 8.2 mg/dL, phosphate 4.8 mg/dL, PTH 142 pg/mL, and urinary calcium 320 mg/24h. Neck ultrasound demonstrates hyperplasia of all four parathyroid glands. He denies taking thiazide diuretics. Which genetic syndrome is most consistent with his presentation?
Answer choices
- AHypoparathyroidism with PTH resistance
- BMEN 1 syndrome with parathyroid adenoma
- CPrimary hyperparathyroidism
- DTertiary hyperparathyroidism
- ESecondary hyperparathyroidism from chronic kidney diseaseCorrect answer
- FFamilial hypocalciuric hypercalcemia with activating CASR mutation
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