title: Clinical significance of FGF-23 measurement in dialysis patients.
abstract: OBJECTIVE
  Considering the growing relevance of fibroblast growth factor-23 (FGF-23) in the pathogenesis of chronic kidney disease bone and mineral disorder (CKD-MBD), an analysis was performed to determine the relative importance of C-terminal (cFGF-23) and intact (iFGF-23) assays in assessing CKD-MBD status in the first place and the relationship between FGF-23 and mortality as a secondary aim.
  
  
  METHODS
  In 77 patients (15 peritoneal dialysis and 62 hemodialysis), levels of calcium, phosphate, parathyroid hormone (PTH), 25-hydroxyvitamin- D (25D), 1,25D, FGF-23 (C-terminal and intact molecule) were measured and their correlations were analyzed. The relationship between FGF-23 levels and patient survival was also analyzed.
  
  
  RESULTS
  A significant correlation was found between cFGF-23 and 1,25D, PTH and 25D while iFGF-23 was significantly correlated with phosphate, 25D and PTH. PTH and 1,25D were independent predictors of cFGF-23, while for iFGF-23 independent predictors were phosphate and 25D. No significant relationship was found between FGF-23 and mortality.
  
  
  CONCLUSIONS
  C-terminal or intact FGF-23 levels are weakly correlated and thus not clearly indicative of FGF-23 effects on PTH, P and vitamin D metabolism in dialysis patients. Assays for cFGF-23 and iFGF-23 showed a good correlation, but the intact molecule was not superior in defining interactions with CKD-MBD molecules. Measuring FGF-23 on a regular basis with the current assays in CKD and dialysis patients does not yet seem clinically useful.
authors: Renal Division, S. Paolo Hospital, Milan, Italy. frannyjongbloed@hotmail.com
authors: F
authors: F
authors: Jongbloed
authors: A
authors: A
authors: Galassi
authors: M
authors: M
authors: Cozzolino
authors: R
authors: R
authors: Zietse
authors: G
authors: G
authors: Chiarelli
authors: D
authors: D
authors: Cusi
authors: D
authors: D
authors: Brancaccio
authors: M
authors: M
authors: Gallieni
mesh_terms: D000368:Aged; D015519:Bone Density; D002118:Calcium / Q000097:blood; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000378:metabolism / Q000401:mortality / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010530:Peritoneal Dialysis; D010710:Phosphates / Q000097:blood; D006435:Renal Dialysis; D016019:Survival Analysis; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood
chemical_list: C000717427:FGF23 protein, human; D010281:Parathyroid Hormone; D010710:Phosphates; D014807:Vitamin D; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23; C104450:25-hydroxyvitamin D; D002118:Calcium