Delayed recognition of hypomagnesemia causing refractory Hypocalcemia after Reoperative neck surgery in a resource-limited setting. a case report

Postoperative hypocalcemia following cervical surgery is typically attributed to hypoparathyroidism. However, hypomagnesemia is a reversible cause that impairs parathyroid hormone (PTH) secretion and target-organ responsiveness. We report a 35-year-old woman with recurrent symptomatic hypocalcemia after reoperative neck exploration for recurrent papillary thyroid carcinoma. Despite aggressive calcium and vitamin D supplementation, hypocalcemia persisted with inappropriately suppressed PTH. Due to resource limitations, serum magnesium evaluation was delayed until postoperative day 6, revealing severe hypomagnesemia. Magnesium repletion led to prompt serum calcium improvement and partial PTH recovery. Although the lack of contemporaneous phosphate and serial PTH measurements is a limitation, the rapid clinical response strongly supports a functional hypoparathyroid state. This case emphasizes early magnesium assessment in refractory postoperative hypocalcemia, demonstrating how resource limitations can delay diagnosis and prolong morbidity.