title: Urinary monocyte chemotactic protein 1: marker of renal function decline in diabetic and nondiabetic proteinuric renal disease.
abstract: BACKGROUND
  Reliable biomarkers are needed to identify patients with glomerular disease at risk of progression. Transforming growth factor beta 1 (TGF-β1) and monocyte chemotactic protein 1 (MCP-1) play key roles in promoting renal tissue injury. Whether their urinary measurement adds value to current predictors of progression is uncertain.
  
  
  METHODS
  We enrolled patients with diabetic (n=53) and nondiabetic (n=47) proteinuric renal disease and retrospectively studied their rate of renal function decline over a defined period of 2 years. We simultaneously measured urinary protein, MCP-1 and TGF-β1, standardized to urinary creatinine.
  
  
  RESULTS
  The initial estimated glomerular filtration rate, proteinuria and rate of renal function decline (slope) were 36 ml/min per 1.73 m2, 1.1 g/day and -4.0 ± 7.2 ml/ min per 1.73 m2 year. Median urinary TGF-β1 and MCP- 1 levels were 0.3 (range 0.0-28.1) and 18 (range 3-370) ng/mmol of creatinine, respectively. Urinary protein and MCP-1 to creatinine ratios were associated with slope, and this applied to both diabetic and nondiabetic patients separately. Urinary TGF-β1 showed no relation to slope. However, the majority of its measurements were below the suggested reproducibility threshold. Using linear regression, both normalized urinary protein and MCP-1 were independently associated with the slope. Adding urinary MCP-1 to the model statistically raised the adjusted R2 from 0.35 to 0.40, refining patient risk stratification. Using cutoffs for urinary protein and MCP-1 obtained by receiver operating characteristic curves, the risk of progression was confidently determined in 80% of patients.
  
  
  CONCLUSIONS
  Urinary MCP-1 is a marker of renal function decline in diabetic and nondiabetic proteinuric renal disease, independent of and additive to proteinuria.
authors.affiliation: Nephrology Division, Sacré-Coeur Hospital of Montréal, Montréal, Québec, Canada.
authors.forename: Roberta
authors.initials: R
authors.lastname: Camilla
authors.forename: Soumeya
authors.initials: S
authors.lastname: Brachemi
authors.forename: Vincent
authors.initials: V
authors.lastname: Pichette
authors.forename: Pierre
authors.initials: P
authors.lastname: Cartier
authors.forename: Alexandra
authors.initials: A
authors.lastname: Laforest-Renald
authors.forename: Tara
authors.initials: T
authors.lastname: MacRae
authors.forename: François
authors.initials: F
authors.lastname: Madore
authors.forename: Stéphan
authors.initials: S
authors.lastname: Troyanov
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D015415:Biomarkers / Q000652:urine; D018932:Chemokine CCL2 / Q000652:urine*; D003404:Creatinine / Q000652:urine; D003928:Diabetic Nephropathies / Q000150:complications / Q000503:physiopathology / Q000652:urine*; D018450:Disease Progression; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007668:Kidney / Q000503:physiopathology*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011507:Proteinuria / Q000209:etiology / Q000503:physiopathology / Q000652:urine*; D011792:Quebec; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D053773:Transforming Growth Factor beta1 / Q000652:urine; D055815:Young Adult
chemical_list: D015415:Biomarkers; C111835:CCL2 protein, human; D018932:Chemokine CCL2; C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1; D003404:Creatinine