Background: Renal vasculitis presents as rapidly progressive glomerulonephritis (RPGN) which comprises of a group of conditions characterised by acute kidney failure (AKF), haematuria and proteinuria. Treatment of these conditions comprises steroid and non-steroid agents in combination with plasma exchange in several situations. Although immunosuppression overall has been very successful in treatment of these conditions, many questions remain unanswered in terms of dose and duration of therapy and the use of plasma exchange.
Objectives: To determine the benefits and harms of any intervention for the treatment of renal vasculitis in adults.
Search strategy: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Renal Group Specialised Register, MEDLINE and EMBASE without language restriction, reference lists of articles and abstracts from conference proceedings.
Selection criteria: Randomised controlled trials investigating any intervention for the treatment of in adults.
Data collection and analysis: Two authors independently assessed study quality and extracted data. Statistical analyses were performed using a random effects model and results expressed as risk ratio (RR) with 95% confidence intervals for dichotomous outcomes or mean difference (MD) for continuous outcomes.
Main results: Thirteen studies (702 patients) were included. Plasma exchange as adjunctive therapy significantly reduces the risk of end-stage kidney disease (ESKD) at three months (one study: RR 0.45, 95% CI 0.24 to 0.84) and 12 months (five studies: RR 0.47, CI 0.24 to 0.86). Three studies compared the use of pulse and continuous administration of cyclophosphamide (CPA). Overall analysis showed a significant increase in remission with pulse CPA (2 studies: RR 1.17; 95%CI 1.02-1.35) and fewer relapses with continuous CPA. A single study addressed the use of azathioprine (AZA) after three months of CPA therapy, showing no difference in outcome except for significantly less leukopenia in patients on AZA. One study into the use of antibiotics to prevent relapse in Wegener's granulomatosis failed to show a significant effect.
Authors' conclusions: Plasma exchange is effective in patients with severe ARF secondary to vasculitis. On current data, the use of pulse CPA results in an increased risk of relapse when compared to continuous use but a reduced total dose. The use of cotrimoxazole is likely to be beneficial to prevent relapse of vasculitis. AZA is effective as maintenance therapy once remission has been achieved.