title: Evaluation of urinary biomarkers for the prognosis of drug-associated chronic tubulointerstitial nephritis.
abstract: BACKGROUND
  The efficacy of urinary biomarkers for predicting adverse clinical outcomes in drug-induced chronic tubulointerstitial nephritis (D-CTIN) has not been well described.
  
  
  METHODS
  A total of 54 patients with D-CTIN were prospectively followed-up in this study. The urinary excretion of α1-microglobulin and transforming growth factor-β1 and the activity of urinary N-acetyl-β-D-glucosaminidase (NAG) and matrix metalloproteinases (MMPs) 2 and 9 at baseline were measured. Changes in the estimated glomerular filtration rate (GFR) over a period of 11 to 54 months (median, 38 months) of follow-up were recorded. The efficacy of urinary biomarkers for differentiating patients with various outcomes was tested. Ten patients with IgA nephropathy and 20 healthy volunteers were enrolled as controls.
  
  
  RESULTS
  The areas under the receiver operating characteristic curve for urinary NAG, MMP-9, MMP-2 and α1-microglobulin for predicting deterioration of the estimated GFR were 0.879, 0.867, 0.735 and 0.709, respectively (P < 0.05 for all). Partial regression coefficient results demonstrated that urinary NAG (P = 0.02), MMP-2 (P = 0.046) and MMP-9 (P = 0.041) were inversely correlated with the rate of GFR decline.
  
  
  CONCLUSIONS
  Urinary NAG, MMP-2 and MMP-9 may be considered as possible candidates for forecasting the progression rate of D-CTIN.
authors.affiliation: Renal Division (YS, TS, LQ, XL, LY), Department of Medicine, First Hospital, Institute of Nephrology, Peking University, Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China; and Renal Division (YS, CW), the First Affiliated Hospital of Baotou Medical College, Baotou, China.
authors.forename: Yingjin
authors.initials: Y
authors.lastname: Shi
authors.forename: Tao
authors.initials: T
authors.lastname: Su
authors.forename: Lei
authors.initials: L
authors.lastname: Qu
authors.forename: Caili
authors.initials: C
authors.lastname: Wang
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Li
authors.forename: Li
authors.initials: L
authors.lastname: Yang
mesh_terms: D000328:Adult; D000510:Alpha-Globulins / Q000652:urine*; D015415:Biomarkers / Q000652:urine; D002681:China; D064420:Drug-Related Side Effects and Adverse Reactions; D005260:Female; D005919:Glomerular Filtration Rate; D005922:Glomerulonephritis, IGA / Q000175:diagnosis* / Q000209:etiology / Q000652:urine; D006801:Humans; D006867:Hydrolases / Q000652:urine*; D008297:Male; D008875:Middle Aged; D009395:Nephritis, Interstitial / Q000139:chemically induced / Q000175:diagnosis* / Q000652:urine; D011379:Prognosis; D011446:Prospective Studies; D053773:Transforming Growth Factor beta1 / Q000652:urine*
chemical_list: D000510:Alpha-Globulins; D015415:Biomarkers; D053773:Transforming Growth Factor beta1; C016001:alpha-1-microglobulin; D006867:Hydrolases