A Case of Hypoparathyroidism Developing 35 Years after Total Thyroidectomy

Abstract

A 70-year-old woman who had undergone total thyroidectomy for thyroid cancer 35 years ago and been receiving thyroid hormone replacement therapy prescribed by her family doctor, was admitted to our hospital because of a convulsion and disturbed consciousness after sustaining a head injury. A head CT revealed no abnormalities. Blood examination revealed marked hypocalcemia, and a low intact parathyroid hormone levels. A clinical diagnosis of hypoparathyroidism arising as a complication of total thyroidectomy was made, and calcium and vitamin D supplementation was initiated. After the serum calcium level returned to the normal range, the patient's symptoms disappeared. Postoperative hypoparathyroidism usually occurs in the early phase post thyroid surgery. Herein, we report a rare case of hypoparathyroidism developing a long time after thyroid surgery.