title: Hepcidin--a potential novel biomarker for iron status in chronic kidney disease.
abstract: OBJECTIVE
  Hepcidin is a key regulator of iron homeostasis, but its study in the setting of chronic kidney disease (CKD) has been hampered by the lack of validated serum assays.
  
  
  METHODS
  This study reports the first measurements of bioactive serum hepcidin using a novel competitive ELISA in 48 pediatric (PCKD2-4) and 32 adult (ACKD2-4) patients with stages 2 to 4 CKD along with 26 pediatric patients with stage 5 CKD (PCKD5D) on peritoneal dialysis.
  
  
  RESULTS
  When compared with their respective controls (pediatric median = 25.3 ng/ml, adult = 72.9 ng/ml), hepcidin was significantly increased in PCKD2-4 (127.3 ng/ml), ACKD2-4 (269.9 ng/ml), and PCKD5D (652.4 ng/ml). Multivariate regression analysis was used to assess the relationship between hepcidin and indicators of anemia, iron status, inflammation, and renal function. In PCKD2-4 (R(2) = 0.57), only ferritin correlated with hepcidin. In ACKD2-4 (R(2) = 0.78), ferritin and soluble transferrin receptor were associated with hepcidin, whereas GFR was inversely correlated. In PCKD5D (R(2) = 0.52), percent iron saturation and ferritin were predictors of hepcidin. In a multivariate analysis that incorporated all three groups (R(2) = 0.6), hepcidin was predicted by ferritin, C-reactive protein, and whether the patient had stage 5D versus stages 2 to 4 CKD.
  
  
  CONCLUSIONS
  These findings suggest that increased hepcidin across the spectrum of CKD may contribute to abnormal iron regulation and erythropoiesis and may be a novel biomarker of iron status and erythropoietin resistance.
authors.affiliation: Department of Pediatrics, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California, USA. jzaritsky@mednet.ucla.edu
authors.forename: Joshua
authors.initials: J
authors.lastname: Zaritsky
authors.forename: Brian
authors.initials: B
authors.lastname: Young
authors.forename: He-Jing
authors.initials: HJ
authors.lastname: Wang
authors.forename: Mark
authors.initials: M
authors.lastname: Westerman
authors.forename: Gordana
authors.initials: G
authors.lastname: Olbina
authors.forename: Elizabeta
authors.initials: E
authors.lastname: Nemeth
authors.forename: Tomas
authors.initials: T
authors.lastname: Ganz
authors.forename: Seth
authors.initials: S
authors.lastname: Rivera
authors.forename: Allen R
authors.initials: AR
authors.lastname: Nissenson
authors.forename: Isidro B
authors.initials: IB
authors.lastname: Salusky
mesh_terms: D000293:Adolescent; D000328:Adult; D023181:Antimicrobial Cationic Peptides / Q000032:analysis* / Q000097:blood*; D015415:Biomarkers / Q000097:blood*; D002097:C-Reactive Protein / Q000378:metabolism; D002648:Child; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods* / Q000592:standards; D004920:Erythropoiesis; D005260:Female; D005293:Ferritins / Q000097:blood; D005919:Glomerular Filtration Rate; D064451:Hepcidins; D006801:Humans; D007501:Iron / Q000378:metabolism*; D033862:Iron-Binding Proteins / Q000097:blood; D008297:Male; D015999:Multivariate Analysis; D010530:Peritoneal Dialysis; D011237:Predictive Value of Tests; D011956:Receptors, Cell Surface / Q000097:blood; D051436:Renal Insufficiency, Chronic / Q000097:blood* / Q000628:therapy; D015203:Reproducibility of Results; D055815:Young Adult
chemical_list: D023181:Antimicrobial Cationic Peptides; D015415:Biomarkers; C578702:HAMP protein, human; D064451:Hepcidins; D033862:Iron-Binding Proteins; D011956:Receptors, Cell Surface; C027293:ferritin receptor; D002097:C-Reactive Protein; D005293:Ferritins; D007501:Iron