title: Circulating C3 levels predict renal and global outcome in patients with renal vasculitis.
abstract: Several studies have demonstrated the crucial role of complement activation in the pathogenesis of ANCA-associated vasculitis. We aimed to assess the association between baseline serum C3 (sC3) levels and long-term outcomes in patients with renal vasculitis. This retrospective study included 111 patients with renal vasculitis from three hospitals who underwent a renal biopsy between 1997 and 2014. Serum levels of C3 were measured at the onset and the study population was divided into three tertiles according to sC3 concentrations (tertile 1 <106 mg/dl; tertile 2 106-128 mg/dl; tertile 3 >128 mg/dl). Patients with lower sC3 (tertile 1) were compared with those having higher levels of sC3 (tertile 2 and tertile 3). Histological, clinical, and laboratory data were recorded for analysis. The primary end point was the composite of end-stage renal disease (ESRD) and death from any cause. Lower sC3 levels were associated with a higher need for dialysis and lower response rate to treatment (p = 0.04 and p = 0.007, respectively). Renal and global survival at 1 and 5 years was 53 and 46 % in patients with lower sC3 (tertile 1) compared with 72 and 65 % in patients with higher sC3 (upper two tertiles) (p = 0.04). In a multivariate Cox-regression model, when adjusted by renal function and histopatholologic categories, lower sC3 remained as an independent predictor of ESRD and death (HR, 1.9; 95 % CI, 1.1 to 3.4; p = 0.02). Baseline serum C3 levels have an independent prognostic value in predicting long-term renal and global survival in patients with renal vasculitis.
authors: Nephrology Department, Hospital Universitario Fundacion, Alcorcon, Spain. jvillacorta@fhalcorcon.es.
authors: Javier
authors: J
authors: Villacorta
authors: Pathology Department, Hospital Virgen de la Salud, Toledo, Spain.
authors: Francisco
authors: F
authors: Diaz-Crespo
authors: Nephrology Department, Hospital Virgen de la Salud, Toledo, Spain.
authors: Mercedes
authors: M
authors: Acevedo
authors: Nephrology Department, Hospital Universitario Doce de Octubre, Madrid, Spain.
authors: Teresa
authors: T
authors: Cavero
authors: Pathology Department, Hospital Universitario Fundacion, Alcorcon, Spain.
authors: Carmen
authors: C
authors: Guerrero
authors: Nephrology Department, Hospital Universitario Doce de Octubre, Madrid, Spain.
authors: Manuel
authors: M
authors: Praga
authors: Nephrology Department, Hospital Universitario Fundacion, Alcorcon, Spain.
authors: Gema
authors: G
authors: Fernandez-Juarez
mesh_terms: D000328:Adult; D000368:Aged; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000378:metabolism; D003176:Complement C3 / Q000378:metabolism*; D003181:Complement C4 / Q000378:metabolism; D018450:Disease Progression; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007668:Kidney / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D014657:Vasculitis / Q000097:blood / Q000378:metabolism* / Q000473:pathology
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D003176:Complement C3; D003181:Complement C4
keywords: Biomarkers; Methodology; Rheumatic diseases; Rheumatic diseases, small vessel vasculitis; Vasculitis