DOI:10.1590/S1807-59322011000300012 CLINICS 2011;66(3):431-435 CLINICAL SCIENCE Parathyroidectomy after kidney transplantation: short- and long-term impact on renal function Gustavo Fernandes Ferreira,I Fabio Luiz de Menezes Montenegro,II David Jose Machado,I Luiz Estevam Ianhez,I William Carlos Nahas,I Elias David-NetoI I Renal Transplant Unit, Faculdade de Medicina da Universidade de S a˜o Paulo, S a˜o Paulo, Brazil. II Department of Head and Neck Surgery, Faculdade de Medicina da Universidade de S a˜o Paulo, S a˜o Paulo, Brazil. INTRODUCTION: Kidney transplantation corrects endocrine imbalances. Nevertheless, these early favorable events are not always followed by rapid normalization of parathyroid hormone secretion. A possible deleterious effect of parathyroidectomy on kidney transplant function has been reported. This study aimed to compare acute and long- term renal changes after total parathyroidectomy with those occurring after general surgery. MATERIALS AND METHODS: This was a retrospective case-controlled study. Nineteen patients with persistent hyperparathyroidism underwent parathyroidectomy due to hypercalcemia. The control group included 19 patients undergoing various general and urological operations. RESULTS: In the parathyroidectomy group, a significant increase in serum creatinine from 1.58 to 2.29 mg/dl (P , 0.05) was noted within the first 5 days after parathyroidectomy. In the control group, a statistically insignificant increase in serum creatinine from 1.49 to 1.65 mg/dl occurred over the same time period. The long-term mean serum creatinine level was not statistically different from baseline either in the parathyroidectomy group (final follow-up creatinine = 1.91 mg/dL) or in the non-parathyroidectomy group (final follow-up creatinine = 1.72 mg/dL). CONCLUSION: Although renal function deteriorates in the acute period following parathyroidectomy, long-term stabilization occurs, with renal function similar to both preoperative function and to a control group of kidney- transplanted patients who underwent other general surgical operations by the final follow up. KEYWORDS: Kidney Transplant; Parathyroid Hormone; Parathyroidectomy; Renal Function; Surgery. Ferreira GF, Montenegro FLM, Machado DJ, Ianhez LE, Nahas WC, David-Neto E. Parathyroidectomy after kidney transplantation: short- and long- term impact on renal function. Clinics. 2011;66(3):431-435. Received for publication on September 24, 2010; First review completed on November 1, 2010; Accepted for publication on November 30, 2010 E-mail: gustavofferreira@gmail.com Tel.: 55 11 35393637 INTRODUCTION Secondary hyperparathyroidism (HPT) is an almost universal complication in patients with chronic renal failure. Successful kidney transplantation corrects endocrine and metabolic imbalances and the main abnormalities respon- sible for secondary HPT in the first months following surgery.1 Nevertheless, these early favorable events are not always followed by a rapid normalization of parathyroid hormone (PTH) secretion. Elevated PTH levels are observed in up to 25% of patients one year after transplantation, despite adequate renal function.2 A subgroup of these patients will ultimately require parathyroidectomy. A possible deleterious effect of parathyroidectomy on kidney transplant function was reported.3 Evidence of an acute effect of parathyroidectomy without significant Copyright 2011 CLINICS – This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non- commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 431 compromise in the long run was reported.4 In one study, the only parameter observed to correlate with an acute decrease in renal function was an acute reduction in PTH.5 In one study of successfully kidney-transplanted indivi- duals, renal changes after total parathyroidectomy with immediate autograft, which were estimated by variation in creatinine level, differed in comparison to changes in kidney transplant patients undergoing other head and neck proce- dures.6 In that study, the control group included only a small number of patients, and observation was restricted to the first days after the operation. These aspects limit the conclusions that can be drawn regarding the long-term safety of total parathyroidectomy in the management of persistent HPT after kidney transplantation. Although kidney dysfunction has also been described in patients undergoing subtotal parathyroidectomy,7 one study sug- gested the superiority of this technique over total parathyr- oidectomy with autotransplantation in the management of persistent HPT after kidney transplantation.8 For some renal transplant patients, it was recommended that total para- thyroidectomy should be avoided to avoid compromising long-term renal function.8