Treatment of Persistent Hypercalcemia and Hyperparathyroidism With Cinacalcet After Successful Kidney Transplantation

Introduction. Hypercalcemia caused by persistent hyperparathyroidism after successful kidney transplantation (KT) is a common problem and may negatively affect graft function, bone metabolism and the cardiovascular system. Cinacalcet is a novel, available tool to control hypercalcemia after KT. The aim of the study was to examine the efficacy of cinacalcet in lowering calcium in KT recipients with persistent hypercalcemia owing to hyperparathyroidism. Methods. In this retrospective observational study, we analyzed 30 patients with persistent hypercalcemia >10.8 mg/dL. All patients in the study were started on cinacalcet at different points after KT, with the mean time of 43 37 months. The initial dose of 30 mg/d was adapted progressively based on serum calcium levels. Results. During the observation period, graft function in all patients was stable (estimated glomerular filtration rate [Chronic Kidney Disease Epidemiology Collaboration formula] 64 +/- 25 mL/min/1.73 m(2)). The mean baseline calcemia was 11.9 +/- 0.7 mg/dL, the intact parathyroid hormone value was 490 +/- 228 pg/mL and phosphorus concentration was 2.2 +/- 0.5 mg/dL. Treatment with cinacalcet resulted in a significant decrease in serum calcium level (mean, 9.9 +/- 0.7 mg/dL; P < .001), a reduction in intact parathyroid hormone level (308 +/- 199 pg/dL; P < .001), and an increase in phosphorus concentration (mean, 2.8 +/- 0.6 mg/dL; P < .001). In 5 females, gastrointestinal side effects were observed, requiring withdrawal of cinacalcet in 1 case. Conclusions. Cinacalcet administered after KT seems to be an effective option for the management of persistent hypercalcemia owing to hyperparathyroidism with satisfactory tolerability and may be considered as a therapeutic alternative to surgical parathyroidectomy or as a bridging therapy to parathyroidectomy.