Predictors of treatment outcomes in ANCA-associated vasculitis with severe kidney failure

• Published in: Clinical journal of the American Society of Nephrology Vol. 9; no. 5; pp. 905 - 913
• Main Authors: Lee, Taewoo, Gasim, Adil, Derebail, Vimal K, Chung, Yunro, McGregor, JulieAnne G, Lionaki, Sophia, Poulton, Caroline J, Hogan, Susan L, Jennette, J Charles, Falk, Ronald J, Nachman, Patrick H
• Format: Journal Article
• Language: English
• Published: United States American Society of Nephrology 01.05.2014
• Subjects: Aged; Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis - complications; Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis - drug therapy; Cyclophosphamide - therapeutic use; End Stage Liver Disease - etiology; End Stage Liver Disease - physiopathology; End Stage Liver Disease - therapy; Female; Glomerular Filtration Rate; Glomerulonephritis - complications; Glomerulonephritis - drug therapy; Glomerulonephritis - pathology; Glomerulonephritis - physiopathology; Glucocorticoids - therapeutic use; Humans; Immunosuppressive Agents - therapeutic use; Kidney Glomerulus - pathology; Male; Middle Aged; Original; Renal Dialysis; Retrospective Studies; Risk Factors; Severity of Illness Index; Survival Rate; Time Factors; Treatment Outcome; glomerulonephritis; ANCA; vasculitis
• DOI: 10.2215/CJN.08290813
• ISSN: 1555-9041

In ANCA-associated GN, severe renal dysfunction portends a poor prognosis for renal recovery and patient survival. This study evaluated the prognostic factors affecting renal and patient outcomes in patients presenting with severe kidney failure to guide immunosuppressive therapy. This study retrospectively evaluated clinical and histopathologic characteristics of 155 patients who underwent biopsy between October 1985 and February 2011 (median eGFR at presentation, 7.1 ml/min per 1.73 m(2); 87% required hemodialysis), all treated with immunosuppressive medications. Three outcomes of interest were measured: patient survival, renal survival, and treatment response (defined as dialysis-free survival without active vasculitis by 4 months after biopsy). Competing risk, Cox, and logistic regression analyses were conducted for each outcome measure. Within 4 months after biopsy, treatment response was attained in 51% of patients, 35% remained on dialysis, and 14% died. In a competing risk analysis, estimated cumulative incidence rates of ESRD and disease-related mortality were 26% and 17% at 1 year and 32% and 28% at 5 years, respectively. Cyclophosphamide therapy and treatment response by 4 months were independently associated with patient and renal survival, adjusting for the percentage of normal glomeruli, histopathologic chronicity index score, and baseline clinical characteristics. Only 5% of patients still dialysis dependent at 4 months subsequently recovered renal function. Low chronicity index score (odds ratio [OR], 1.16; 95% confidence interval [95% CI], 1.04 to 1.30, per unit decrease) and baseline eGFR>10 ml/min per 1.73 m(2) (OR, 2.77; 95% CI, 1.09 to 7.01) were significantly associated with treatment response by 4 months. Among cyclophosphamide-treated patients, the likelihood of treatment response was >14% even with highest chronicity index score and eGFR<10 ml/min per 1.73 m(2). Although low baseline renal function and severe renal scarring are associated with lower treatment response rate, no "futility" threshold could be identified. Conversely, continued immunosuppressive therapy beyond 4 months is unlikely to benefit patients who remain dialysis dependent.