Calcium and Parathyroid USMLE Step 1 Practice Question
A 57-year-old woman with symptomatic primary hyperparathyroidism presents with muscle weakness and cognitive changes. Vital signs: BP 138/88, HR 92, RR 16, Temp 37°C. Labs show serum calcium 11.8 mg/dL and alkaline phosphatase 78 U/L. Imaging confirms a solitary left parathyroid adenoma. She denies recent diuretic use. Surgical removal is planned. Which of the following laboratory values would most likely have been elevated preoperatively?
Answer choices
- AUrinary cyclic AMPCorrect answer
- BSerum calcitonin
- CUrinary metanephrines
- DSerum phosphate
- EPlasma renin activity
- FUrinary hydroxyproline elevated from osteoclastic bone resorption
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