title: Early postoperative C-terminal agrin fragment (CAF) serum levels predict graft loss and proteinuria in renal transplant recipients.
abstract: BACKGROUND
  C-terminal agrin fragment (CAF), cleavage product of agrin, was previously correlated with kidney function in renal transplant patients. This article studies the predictive value of CAF for long-term outcomes in renal transplant recipients.
  
  
  METHODS
  In this observational cohort study, serum CAF, creatinine and blood-urea-nitrogen (BUN) concentrations and eGFR (CKD-EPI) were assessed 1-3 months after transplantation in 105 patients undergoing kidney transplantation. Cox regression models were used to analyse the predictive value of all parameters concerning all-cause mortality (ACM), graft loss (GL), doubling of creatinine/proteinuria at the end of follow-up.
  
  
  RESULTS
  Median follow-up time was 3.1 years. The mean concentrations were 191.9±152.4 pM for CAF, 176±96.8 μmol/L for creatinine, 12.6±6.2 mmol/L for BUN and 44.9±21.2 mL/min for CKD-EPI formula, respectively. In univariate analysis CAF and BUN concentrations predicted ACM (CAF: HR=1.003, 1.1-fold risk, p=0.043; BUN: HR=1.037, 1.3-fold risk, p=0.006). Concerning GL, CAF (HR=1.006, 3.1-fold risk, p<0.001), creatinine (HR=2.396, 2.6-fold risk, p<0.001), BUN (HR=1.048, 1.7-fold risk, p=0.001) and eGFR (CKD-EPI) (HR=0.941, 0.45-fold risk reduction, p=0.006) showed a statistically significant association. CAF was the only parameter significantly associated with doubling of proteinuria (HR=1.005, 1.7-fold risk, p<0.001). In multiple regression analysis (CAF only) the association remained significant for GL and doubling of proteinuria but not ACM.
  
  
  CONCLUSIONS
  Early postoperative serum CAF appears to be a useful tool for the assessment of long-term outcomes in renal transplant recipients. Most importantly it represents a promising predictor for the development of proteinuria.
authors.forename: Dominik
authors.initials: D
authors.lastname: Steubl
authors.forename: Anna
authors.initials: A
authors.lastname: Vogel
authors.forename: Stefan
authors.initials: S
authors.lastname: Hettwer
authors.forename: Susanne
authors.initials: S
authors.lastname: Tholen
authors.forename: Peter B
authors.initials: PB
authors.lastname: Luppa
authors.forename: Ina-Christine
authors.initials: IC
authors.lastname: Rondak
authors.forename: Lutz
authors.initials: L
authors.lastname: Renders
authors.forename: Uwe
authors.initials: U
authors.lastname: Heemann
authors.forename: Marcel
authors.initials: M
authors.lastname: Roos
mesh_terms: D018171:Agrin / Q000097:blood*; D001806:Blood Urea Nitrogen; D015331:Cohort Studies; D003404:Creatinine / Q000097:blood; D005260:Female; D005919:Glomerular Filtration Rate; D006084:Graft Rejection / Q000097:blood* / Q000175:diagnosis*; D006085:Graft Survival; D006801:Humans; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000097:blood*; D011507:Proteinuria / Q000097:blood* / Q000175:diagnosis*
chemical_list: D018171:Agrin; C000602450:C-terminal agrin fragment; D010446:Peptide Fragments; D003404:Creatinine