Three days after parathyroidectomy for severe primary hyperparathyroidism, a 46-year-old woman develops perioral tingling, Chvostek sign, and carpopedal spasm. Calcium is 6.8 mg/dL, phosphate 1.8 mg/dL, and PTH is undetectable. Preoperative alkaline phosphatase had been markedly elevated. What is the most appropriate treatment?

• A IV furosemide to accelerate calcium excretion
• B Oral cholecalciferol 60,000 IU weekly
• C Reoperation for recurrent laryngeal nerve injury
• D IV calcium gluconate plus oral calcitriol ✓

Explanation

This is hungry bone syndrome: after removal of the PTH source, severely depleted bone avidly takes up calcium and phosphate, producing profound hypocalcaemia with hypophosphataemia and tetany, particularly when preoperative alkaline phosphatase was high. Symptomatic hypocalcaemia requires IV calcium gluconate, and because PTH-dependent renal activation of vitamin A is absent, calcitriol rather than cholecalciferol is needed. Furosemide would lower calcium further.

Reference: Williams Textbook of Endocrinology, 14th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.