Calcium and Parathyroid USMLE Step 1 Practice Question
A 34-year-old man with end-stage renal disease on hemodialysis presents with progressive bone pain and muscle weakness. Vital signs: BP 146/92 mmHg, HR 88/min, RR 16/min, temp 37.2°C. Serum calcium is 10.9 mg/dL, PTH 410 pg/mL (normal 15-65), alkaline phosphatase elevated at 95 U/L, and phosphate 6.2 mg/dL. Recent parathyroid ultrasound shows bilateral gland enlargement. He denies chest pain. Which of the following is the most appropriate next step?
Answer choices
- APrescribe calcium channel blockers
- BParathyroidectomyCorrect answer
- CInitiate phosphate binders alone
- DIncrease dialysate calcium concentration
- EStart vitamin D supplementation
- FAdminister intravenous calcitriol and optimize dialysis parameters
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