Kinetics of parathyroid hormone after parathyroidectomy in chronic hemodialysis patients

Abstract

Secondary hyperparathyroidism is a common complication in chronic renal failure. The treatment in some cases requires parathyroidectomy. The kinetics of the parathyroid hormone (PTH) levels after surgery helps to evaluate the efficacy of parathyroidectomy. Prospective analysis was made of the kinetics of intact PTH (iPTH) after parathyroidectomy in 10 chronic hemodialysis (HD) patients who had secondary hyperparathyroidism. We determined the levels of iPTH before surgery and its evolution after parathyroidectomy at regular intervals: Day 0, D7, D15, D30 and D90. The mean age of our patients was 40 ± 13 years, with a sex ratio of 1. The mean duration on HD was 122 ± 63 months. The duration of secondary hyperparathyroidism varied from one year to 12 years. All patients had received medical treatment for hyperparathyroidism. The indications for parathyroidectomy included resistance to medical treatment in seven cases, development of brown tumors in two cases and soft tissue calcifications in one case. All patients had radiographic evidence of hyperparathyroidism. The parathyroidectomy was sub-total in all patients, 6/8 in four cases and 7/8 in six cases. The mean iPTH level was 2341 ± 1946 pg/mL before surgery. A sharp drop in this level was noticed on D0, with a median of 92 pg/mL and, thereafter, the levels were 79 pg/mL on D7, 25 pg/mL on D15 and 36 pg/mL after 1 month. At 3 months post-surgery, the mean iPTH level was 302 pg/mL. Histological examination of the resected gland showed parathyroid hyperplasia in all patients. In our series, the efficacy of sub-total parathyroidectomy was satisfactory with rapid normalization of PTH, which is consistent with the literature data. Sub-total parathyroidectomy still has a place in the treatment of secondary hyperparathyroidism in chronic renal failure. Its indications should be limited to cases resistant to medical treatment and, in particular, in cases with occurrence of complications.