Electrolyte Disorders USMLE Step 1 Practice Question
A 52-year-old woman with no past medical history presents with progressive fatigue and proximal muscle weakness. Vital signs: BP 138/88 mmHg, HR 92 bpm, RR 16/min, temp 37.2°C. Serum calcium is 11.8 mg/dL with normal albumin. PTH is suppressed at 8 pg/mL. Chest X-ray shows no pulmonary infiltrates. She denies recent medication use or vitamin supplement intake. Which of the following is the most likely cause of her hypercalcemia?
Answer choices
- AFamilial hypocalciuric hypercalcemia
- BVitamin D intoxication
- CMalignancy-related hypercalcemiaCorrect answer
- DPrimary hyperparathyroidism
- EHyperthyroidism
- FSarcoidosis with granulomatous activation of vitamin D
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