Thyroid Disorders USMLE Step 1 Practice Question
A 49-year-old woman presents with perioral numbness and carpopedal spasm 2 days following total thyroidectomy. Vital signs show BP 128/82, HR 88, RR 16, temperature 37.2°C. Physical examination demonstrates facial twitching upon tapping the facial nerve. Laboratory studies reveal serum calcium 7.2 mg/dL (normal 8.5-10.5), phosphate 5.1 mg/dL (normal 2.5-4.5), and intact PTH 18 pg/mL. She denies neck pain. Which of the following is the most likely cause of her symptoms?
Answer choices
- AExcess calcitonin from medullary carcinoma
- BThyroid storm
- CPheochromocytoma
- DAccidental removal or damage to parathyroid glandsCorrect answer
- EGraves ophthalmopathy
- FSurgical injury to the recurrent laryngeal nerve
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