Treatment of Hyperparathyroidism With Cinacalcet in Kidney Transplant Recipients

• Published in: Transplantation proceedings Vol. 42; no. 10; pp. 4078 - 4082
• Main Authors: Borstnar, S, Erzen, B, Gmeiner Stopar, T, Kocjan, T, Arnol, M, Kandus, A, Kovac, D
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier Inc 01-12-2010; Elsevier
• Subjects: Biological and medical sciences; Cinacalcet Hydrochloride; Endocrinopathies; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Humans; Hyperparathyroidism - drug therapy; Kidney Transplantation; Medical sciences; Naphthalenes - therapeutic use; Non tumoral diseases. Target tissue resistance. Benign neoplasms; Parathyroids. Parafollicular cells. Cholecalciferol. Phosphocalcic homeostasis (diseases); Surgery; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Tissue, organ and graft immunology; Endocrinopathy; Calcimimetic agent; Peptide hormone; Transplantation; Antihormone; Homotransplantation; Kidney; Medicine; Treatment; Urinary system; Parathyroid hormone; Parathyroid diseases; Surgery; Graft; Cinacalcet; Hyperparathyroidism
• ISSN: 0041-1345; 1873-2623
• DOI: 10.1016/j.transproceed.2010.09.059

Abstract Background After successful kidney transplantation, hyperparathyroidism can persist in 10%–50% of patients and can harmfully affect bone metabolism. Calcimimetic cinacalcet is a new treatment option in the management of persistent hyperparathyroidism in these patients. Methods This prospective, clinical study of 11 patients included those who had a serum intact parathyroid hormone (iPTH) concentration >65 ng/L, a serum creatinine concentration was <200 μmol/L, stable kidney graft function, and were >1 year since transplantation. Patients were not treated with drugs other than calcitriol that could influence bone metabolism. During the 6-month observation period, in which the stability of measured parameters was determined, and in the 12-month treatment period (cinacalcet 30 mg/d), we followed serum concentrations of calcium, phosphate, iPTH, creatinine, vitamin 25OH D3 , bone-specific alkaline phosphatase (ALP), osteocalcin, collagen degradation fragments (CTX), urinary calcium excretion, and bone mineral density (BMD). Results During the treatment period, the serum calcium concentration decreased significantly (from 2.50 ± 0.12 to 2.32 ± 0.12 mmol/L; P < .01). Serum iPTH concentration decreased significantly (from 247 [range, 199–362] at time 0 to 198 [range, 165–233] ng/L after 1 month of treatment; P < .05), but increased slightly thereafter. After 6 months of treatment, the serum concentration of ALP and CTX increased significantly, but decreased thereafter. There were no significant changes in the other parameters assessed. Renal function remained stable during the treatment period. The BMD of the lumbar spine, hip, and forearm did not change during the 12 months of treatment. Conclusion Cinacalcet was effective in treating posttransplant hyperparathyroidism, resulting in decreased calcemia and transient decreased iPTH. ALP and CTX transiently increased during therapy, but other markers of bone metabolism remained unchanged. Twelve months of cinacalcet treatment did not result in a change in BMD. Cinacalcet seems to be a safe drug with no negative effect on renal function.