Thyroid Disorders USMLE Step 1 Practice Question
A 12-year-old boy presents with muscle cramps, paresthesias, and a history of developmental delay. Vital signs: BP 118/76 mmHg, HR 88 bpm, RR 16/min, Temp 37Ā°C, SpO2 98% on room air. Physical examination reveals short fourth and fifth metacarpals bilaterally and mild facial dysmorphism. Laboratory studies demonstrate 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
- ADiGeorge syndrome
- BPseudohypoparathyroidismCorrect answer
- CPrimary hyperparathyroidism
- DVitamin D deficiency
- EHypoparathyroidism after thyroid surgery
- FAutosomal dominant hypocalcemia due to calcium-sensing receptor mutation
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