Plasma Exchange for Renal Vasculitis and Idiopathic Rapidly Progressive Glomerulonephritis: A Meta-analysis

Abstract

Background Plasma exchange may be effective adjunctive treatment for renal vasculitis. We performed a systematic review and meta-analysis of randomized control trials of plasma exchange for renal vasculitis. Study Design Systematic review and meta-analysis of manuscripts identified from electronic databases, bibliographies, and studies identified by experts. Data was abstracted in parallel by two reviewers. Setting & Population Adults with idiopathic renal vasculitis or rapidly progressive glomerulonephritis Selection Criteria for Studies Randomized controlled trials that compared standard care with standard care plus adjuvant plasma exchange in adult patients with either renal vasculitis or idiopathic rapidly progressive glomerulonephritis. Intervention Adjuvant plasma exchange Outcome Composite of end-stage renal disease or death. Results We identified 9 trials including 387 patients. In a fixed-effects model the pooled relative risk of end-stage renal disease or death was 0.80 for patients treated with adjunctive plasma exchange compared to standard care alone (95% confidence interval 0.65 to 0.99; p=0.04). No significant heterogeneity was detected (p=0.5; I2=0%). The effect of plasma exchange did not differ significantly across the range of baseline serum creatinine values (p=0.7) or number of plasma exchange treatments (p=0.8). The relative risk for end-stage renal disease was 0.64 (95% confidence interval 0.47 to 0.88; p=0.006) while the relative risk for death alone was 1.01 (95% confidence interval 0.71 to 1.4; p=0.9). Limitations Although the primary result was statistically significant, there is insufficient statistical information to reliable determine if plasma exchange reduces the composite of end-stage renal disease or death. Conclusions Plasma exchange may reduce the composite endpoint of end-stage renal disease or death in renal vasculitis. Further trials are required given the limited data available.