Calcium and Parathyroid USMLE Step 1 Practice Question
A 14-year-old girl presents with progressive muscle cramps and perioral paresthesias. Vital signs: BP 118/76, HR 88, RR 16, Temp 37°C, SpO2 98%. Physical examination reveals short stature, central obesity, and shortened fourth and fifth metacarpals bilaterally. Laboratory studies show serum calcium 7.2 mg/dL, phosphate 5.8 mg/dL, and PTH 156 pg/mL. Thyroid function tests are normal. Which of the following is the most likely diagnosis?
Answer choices
- APrimary hyperparathyroidism
- BFamilial hypocalciuric hypercalcemia
- CHypoparathyroidism
- DPseudohypoparathyroidismCorrect answer
- EVitamin D deficiency
- FSecondary hyperparathyroidism due to chronic kidney disease
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