title: FGF-23, α-Klotho Gene Polymorphism and Their Relationship with the Markers of Bone Metabolism in Chronic Peritoneal Dialysis Patients.
abstract: OBJECTIVE
  The aim of the present study was to evaluate the variations of some major bone metabolism markers with reference to klotho gene polymorphism (KGP) and bone mineral density (BMD) values in patients on chronic peritoneal dialysis (CPD).
  
  
  METHODS
  In 51 CPD patients and 40 healthy persons, assays for intact parathormone (iPTH), fibroblast growth factor 23 (FGF-23), osteoprotegerin (OPG), osteocalcin (OC), procollagen type-1 N terminal propeptide (PINP), beta- crosslaps (beta CTx), tartrate resistant acid phosphatase (TRAP5b), bone alkaline phosphatase (BAP), 1,25(OH)D3, and 25(OH)D3 and α-klotho gene mutations were performed.
  
  
  RESULTS
  In CPD patients, 1,25(OH)D3 and 25(OH)D3 deficiency rates were 96% and 94% respectively. iPTH (249 pg/mL vs 39 pg/mL) and FGF-23 (1089 RU/mL vs 153 RU/mL), OPG, OC, PINP, beta CTx, TRAP5b levels were significantly higher in patients. iPTH levels and whole-body BMD values were negatively correlated in patients. The rate of KGP was similar in all groups.
  
  
  CONCLUSIONS
  In CPD patients, besides vitamin D deficiency, high levels of OPG, OC, PINP, beta CTx, TRAP5b were evident. Positive correlation between iPTH levels and BAP and PINP levels suggested a diagnostic value for those markers during the management of CKD MBD. On the other hand, high serum TRAP5b concentrations did not seem to be affected by neither calcitriol treatment nor the severity of hyperparathyroidism. iPTH and FGF-23 levels and whole-body BMD values showed a significant negative correlation. We were unable to show any correlation between KGP and any of the CKD-MBD parameters measured in this study.
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Akdeniz University Faculty of Medicine, Antalya, Turkey.
authors.forename: Vural Taner
authors.initials: VT
authors.lastname: Yilmaz
authors.affiliation: Department of Biochemistry, Akdeniz University Faculty of Medicine, Antalya, Turkey.
authors.forename: Sebahat
authors.initials: S
authors.lastname: Ozdem
authors.affiliation: Department of Public Medicine, Akdeniz University Faculty of Medicine, Antalya, Turkey.
authors.forename: Levent
authors.initials: L
authors.lastname: Donmez
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Akdeniz University Faculty of Medicine, Antalya, Turkey.
authors.forename: Ramazan
authors.initials: R
authors.lastname: Cetinkaya
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Akdeniz University Faculty of Medicine, Antalya, Turkey.
authors.forename: Gultekin
authors.initials: G
authors.lastname: Suleymanlar
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Akdeniz University Faculty of Medicine, Antalya, Turkey.
authors.forename: F Fevzi
authors.initials: FF
authors.lastname: Ersoy
keywords: Peritoneal dialysis; beta CTx; bone mineral density; fibroblast growth factor 23; klotho gene polymorphism