Delayed recovery from post-thyroidectomy hypoparathyroidism: a case report

Thirteen hours after a subtotal thyroidectomy was performed for hyperthyroidism, a patient developed carpopedal spasms, parathesias and hypocalcemia to 6.9 mg/dL. After initial stabilization with intravenous calcium administration, oral calcium carbonate and calcitriol were required. Ten months postoperatively serum calcium levels rose and supplementation was gradually discontinued. The serum parathyroid hormone (PTH) level was 1.0 pg/mL on the second postoperative day and levels were undetectable despite sensitive testing 3 months later (normal 10-65 pg/mL). Two years after surgery, the PTH level has increased to 36 pg/mL, but remains relatively low considering the patient's continued mild hypocalcemia. To our knowledge, there has been no previously reported case of long-term post-thyroidectomy hypocalcemia documenting undetectable parathyroid function and subsequent spontaneous improvement. This case suggests that delayed recovery of parathyroid function and discontinuation of vitamin D and calcium supplementation may be possible in some post-thyroidectomy patients with hypocalcemia due to severe hypoparathyroidism.