The Therapeutic Effect Of Plasma Exchange On Anca-Associated Vasculitis: A Meta-Analysis

Aims: The therapeutic effect of plasma exchange (PLEX) combined with conventional treatment in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) remains controversial. Materials and methods: We searched PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure for randomized controlled trials (RCTs) and cohort studies that compared PLEX added to conventional therapy with conventional therapy only in active AAV. Results: 19 studies were included for the meta-analysis. Compared with the conventional therapy group, the PLEX group had a significantly reduced risk of end-stage renal disease (ESRD) at 3 months (odds ratio (OR) = 0.32, 95% confidence interval (CI) = 0.16 - 0.66, p = 0.002, I-2 = 0%), and the ANCA titerwas also decreased (OR = 40.99, 95% Cl = 23.56 - 58.43, p < 0.00001, I-2 = 42%). The plasma and non-plasma exchange groups had no substantial differences in terms of short- and long-term outcomes, including all-cause mortality, ESRD risk at 12 months and 5 years, remission rate, serum creatine levels, or serious adverse events. Conclusion: PLEX therapy was not associated with favorable long-term outcomes, although the results showed benefits in the incidence of ESRD rate at 3 months and ANCA titers in patients with AAV. No advantage of PLEX added to conventional therapy on mortality and complete remission was observed in patients with diffuse alveolar hemorrhage. Further high-quality multicenter RCTs with a high number of participants are required to assess the potential efficacy of PLEX in active AAV.