title: Prognostic value of risk score and urinary markers in idiopathic membranous nephropathy.
abstract: OBJECTIVE
  Accurate prediction of prognosis may improve management of patients with idiopathic membranous nephropathy. This study compared the Toronto Risk Score and urinary low-molecular weight proteins.
  
  
  METHODS
  One hundred four patients with biopsy-proven idiopathic membranous nephropathy who presented between 1995 and 2008 with a well-preserved kidney function and nephrotic range proteinuria were included. Urinary β2-microglobulin and α1-microglobulin measurements were obtained by timed standardized measurements, and the Toronto Risk Score was calculated using data obtained from medical records. The endpoint was progression, which was defined as an increase in serum creatinine > 50% or > 25% with a concentration > 135 μmol/L.
  
  
  RESULTS
  Forty-nine patients showed progression. The area under the receiver-operating characteristics curve was 0.78 (95% confidence interval = 0.69-0.88) for the risk score versus 0.80 (0.71-0.89) and 0.79 (0.71-0.88) for urinary β2- and α1-microglobulin, respectively. Differences were not significant. Persistent proteinuria did not add accuracy to the Toronto Risk Score. Conversely, its accuracy was not reduced when data from the first 6 months of follow-up were used. Furthermore, a score based on GFR estimated with the six-variable Modification of Diet in Renal Disease equation, calculated in the first 6 months of follow-up, gave an area under the receiver-operating characteristics curve of 0.83 (0.74-0.92), which was not statistically different from other markers.
  
  
  CONCLUSIONS
  The prognostic accuracies of the Toronto Risk Score and urinary low-molecular weight proteins were not significantly different. The risk score can be calculated within 6 months of diagnosis, and a simplified risk score using estimated GFR-Modification of Diet in Renal Disease may be sufficient.
authors.affiliation: Department of Nephrology, Radboud University Medical Centre, Nijmegen, The Netherlands. a.vandenbrand@nier.umcn.nl
authors.forename: Jan A J G
authors.initials: JA
authors.lastname: van den Brand
authors.forename: Julia M
authors.initials: JM
authors.lastname: Hofstra
authors.forename: Jack F M
authors.initials: JF
authors.lastname: Wetzels
mesh_terms: D000328:Adult; D000368:Aged; D000510:Alpha-Globulins / Q000652:urine*; D015415:Biomarkers / Q000097:blood / Q000652:urine; D001706:Biopsy; D003404:Creatinine / Q000097:blood; D018450:Disease Progression; D005260:Female; D005919:Glomerular Filtration Rate; D015433:Glomerulonephritis, Membranous / Q000097:blood / Q000175:diagnosis / Q000503:physiopathology / Q000652:urine*; D006801:Humans; D053208:Kaplan-Meier Estimate; D007668:Kidney / Q000503:physiopathology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D011237:Predictive Value of Tests; D011379:Prognosis; D011507:Proteinuria / Q000175:diagnosis / Q000652:urine*; D012372:ROC Curve; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors; D001613:beta 2-Microglobulin / Q000652:urine*
chemical_list: D000510:Alpha-Globulins; D015415:Biomarkers; C016001:alpha-1-microglobulin; D001613:beta 2-Microglobulin; D003404:Creatinine