title: Effect of paricalcitol on mineral bone metabolism in kidney transplant recipients with secondary hyperparathyroidism.
abstract: BACKGROUND
  Secondary hyperparathyroidism is highly prevalent in kidney transplant recipients, and commonly results in hypercalcaemia; an association to osteopenia and bone fractures has also been observed. Paricalcitol has proved effective to control secondary hyperparathyroidism in chronic kidney disease in both dialysed and non-dialysed patients, with a low hypercalcaemia incidence. Currently available experience on paricalcitol use in kidney transplant recipients is scarce. Our main aim was to show the effect of paricalcitol on mineral bone metabolism in kidney transplant recipients with secondary hyperparathyroidism.
  
  
  METHODS
  A retrospective multicentre study in kidney transplant recipients aged>18 years with a 12-month or longer post-transplantation course, stable renal function, having received paricalcitol for more than 12 months, with available clinical follow-up for a 24-month period.
  
  
  RESULTS
  A total of 69 patients with a 120 ± 92-month post-transplantation course were included. Baseline creatinine was 2.2 ± 0.9 mg/dl y GFR-MDRD was 36 ± 20 ml/min/1.73 m(2). Paricalcitol doses were gradually increased during the study: baseline 3.8 ± 1.9 μg/week, 12 months 5.2 ± 2.4 μg/week; 24 months 6.0 ± 2.9 μg/week (P<.001). Serum PTH levels showed a significant fast decline: baseline 288 ± 152 pg/ml; 6 months 226 ± 184 pg/ml; 12 months 207 ± 120; 24 months 193 ± 119 pg/ml (P<.001). Reduction from baseline PTH was ≥30% in 42.4% of patients at 12 months y in 65.2% of patients at 24 months. Alkaline phosphatase showed a significant decrease in first 6 months followed by a plateau: baseline 92 ± 50 IU/l; 6 months 85 ± 36 IU/l, 12 months 81 ± 39 IU/l (P<.001). Overall, no changes were observed in serum calcium and phosphorus, and in urine calcium excretion. PTH decline was larger in patients with higher baseline levels. Patients with lower baseline calcium levels showed significantly increased levels (mean increase was 0.5-0.6 mg/dl) but still within normal range, whereas patients with baseline calcium>10mg/dl showed gradually decreasing levels. Fifteen (21.7%) patients had received prior calcitriol therapy. When shifted to paricalcitol, such patients required paricalcitol doses significantly larger than those not having received calcitriol. Paricalcitol was used concomitantly to cinacalcet in 11 patients with significant PTH reductions being achieved; clinical course was similar to other patients and paricalcitol doses were also similar.
  
  
  CONCLUSIONS
  Paricalcitol is an effective therapy for secondary hyperparathyroidism in kidney transplant recipients. Overall, no significant changes were observed in calcium and phosphorus levels or urinary excretion. Patients having previously received calcitriol required higher paricalcitol doses. When used in patients receiving cinacalcet, paricalcitol results in a significant PTH fall, with paricalcitol doses being similar to those used in patients not receiving cinacalcet.
authors: Servicio de Nefrología, Complejo Hospitalario de Jaén, Jaén, España. Electronic address: fborregou@senefro.org.
authors: Francisco José
authors: FJ
authors: Borrego Utiel
authors: Servicio de Nefrología, Hospital Universitario Virgen de las Nieves, Granada, España.
authors: Juan Antonio
authors: JA
authors: Bravo Soto
authors: Servicio de Nefrología, Hospital Juan Ramón Jiménez, Huelva, España.
authors: María José
authors: MJ
authors: Merino Pérez
authors: Servicio de Nefrología, Hospital Juan Ramón Jiménez, Huelva, España.
authors: Isabel
authors: I
authors: González Carmelo
authors: Servicio de Nefrología, Hospital Regional Carlos Haya, Málaga, España.
authors: Verónica
authors: V
authors: López Jiménez
authors: Servicio de Nefrología, Hospital Puerta del Mar, Cádiz, España.
authors: Teresa
authors: T
authors: García Álvarez
authors: Servicio de Nefrología, Hospital Universitario Virgen del Rocío, Sevilla, España.
authors: Yelenei
authors: Y
authors: Acosta Martínez
authors: Servicio de Nefrología, Hospital Puerta del Mar, Cádiz, España.
authors: María Auxiliadora
authors: MA
authors: Mazuecos Blanca
mesh_terms: D000328:Adult; D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood; D050071:Bone Density Conservation Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D001851:Bone Diseases, Metabolic / Q000209:etiology / Q000517:prevention & control; D001842:Bone and Bones / Q000187:drug effects* / Q000378:metabolism; D002117:Calcitriol / Q000627:therapeutic use; D002118:Calcium / Q000378:metabolism*; D000069449:Cinacalcet / Q000627:therapeutic use; D057915:Drug Substitution; D004359:Drug Therapy, Combination; D004872:Ergocalciferols / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000188:drug therapy* / Q000209:etiology; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010758:Phosphorus / Q000378:metabolism*; D011183:Postoperative Complications / Q000188:drug therapy* / Q000209:etiology; D012189:Retrospective Studies
chemical_list: D050071:Bone Density Conservation Agents; D004872:Ergocalciferols; D007166:Immunosuppressive Agents; D010281:Parathyroid Hormone; D010758:Phosphorus; C084656:paricalcitol; D000469:Alkaline Phosphatase; D002117:Calcitriol; D002118:Calcium; D000069449:Cinacalcet
keywords: Calcitriol; Cinacalcet; Hiperparatiroidismo secundario; Paricalcitol; Renal transplantation; Secondary hyperparathyroidism; Trasplante renal