POS-754 PERSISTENT HYPERPARATHYROIDISM AFTER KIDNEY TRANSPLANTATION, ITS PREVALENCE AND RISK FACTORS

Abstract

Persistent hyperparathyroidism (pHPT) is common after successful kidney transplantation (KTx) and is related to pretransplant risk factors. pHPT is associated with increased graft loss, mortality and increased risk of fractures. This study aims to evaluate the prevalence and risk factors for pHPT after KTx. A retrospective study of kidney transplant recipients attending the transplant clinic between November 2018 and March 2020 was performed. The laboratory data of patients (Serum calcium, phosphorus, creatinine, intact parathyroid hormone (iPTH) and estimated glomerular filtration rate (eGFR)) were collected at 12 months posttransplantation and at pretransplantation. The persistency of HPT after transplant was defined as iPTH ≥ 130 pg/mL, and the term "tertiary hyperparathyroidism" (THPT) was used for patients with pHPT how needed parathyroidectomy (PTx). Risk factors for the development of pHPT were investigated by comparing THPT and non-pHPT groups. Data for 80 patients were analyzed. After one year of KTx, HPT persists in 18 patients (22.5%), of whom six patients underwent parathyroidectomy, and 12 patients were kept on conservative management. Compared with non-HPT group, patients with THPT had significantly longer dialysis duration (43 ± 32.6 mo vs 12.6 ± 13.9 mo. P = 0.013), higher pre-KTx iPTH (1138.7 ± 669.8 vs 365.5 ± 178.6 pg/ml, P = 0.001), and higher pre-KTx calcium (10.1 ± 0.61 vs 8.6 ± 0.60 mg/dl, P < 0.0001). Based on our study results, the most important risk factors for post-KT pHPT are long dialysis duration and high pre-KTx iPTH and Ca levels. Therefore, parathyroidectomy must be considered before kidney transplantation in high-risk patients.