Background: Parathyroid autotransplantation is a well-established method to prevent hypoparathyroidism during parathyroid and thyroid operations. The reported success rate of parathyroid autotransplantation ranges from 75% to 100%. Recurrent hyperparathyroidism may develop after parathyroid autotransplantation, especially after the transplantation of hyperplastic or adenomatous parathyroid tissue. Hyperparathyroidism recurs most frequently after subtotal parathyroidectomy or total parathyroidectomy and autotransplantation, in patients with renal failure and secondary hyperparathyroidism, and in patients with familial primary hyperparathyroidism or MEN I or MEN II syndrome. We report three patients who experienced primary hyperparathyroidism after autotransplantation of normal parathyroid tissue during thyroid operations (two patients) or after a long period of hypoparathyroidism.

Study Design: We reviewed our records from 1983 to May 1998 and identified three patients in whom hyperparathyroidism developed after thyroid operations.

Results: One patient had a thyroidectomy with left modified radical neck dissection for papillary thyroid cancer, followed by radiodine ablative therapy. Two patients had thyroid operations for benign thyroid disease. One of these patients had a history of radiation exposure for acne, and in the other one secondary hyperparathyroidism arose 6 years after a thyroidectomy for hyperthyroidism.

Conclusions: Our study documents that hyperparathyroidism may develop after autotransplantation of histologically normal parathyroid tissue and after a period of hypoparathyroidism after thyroid operations. For this reason, it is important to mark the site of the parathyroid transplantation.