Calcium and Parathyroid USMLE Step 1 Practice Question
A 28-year-old woman with prior thyroidectomy presents with perioral paresthesias and muscle cramps. Vitals: BP 118/76, HR 92, RR 16, Temp 37°C, SpO2 98%. Physical exam reveals positive Chvostek sign; deep tendon reflexes are normal. Labs show serum calcium 7.2 mg/dL, phosphate 6.1 mg/dL, magnesium 1.6 mg/dL, PTH 8 pg/mL, and ionized calcium 3.2 mg/dL. She takes no medications. Which of the following is the most appropriate immediate treatment?
Answer choices
- ASodium phosphate infusion
- BMagnesium sulfate alone
- CIntravenous calcium gluconateCorrect answer
- DLoop diuretics and saline hydration
- EOral vitamin D supplementation
- FIntravenous calcitriol with phosphate binder
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