Clinical, serological and histological determinants of patient and renal outcome in ANCA-associated vasculitis with renal involvement: an analysis from a referral centre

To evaluate significance of clinical and histopathological prognostic factors for renal and patient outcome in AAV patient cohort.

Retrospective study included consecutive patients diagnosed with pauci-immune crescentic glomerulonephritis from January 2003 to December 2013. Primary outcome was combined endpoint patient death or progression to end-stage renal disease (ESRD). Secondary outcomes were patient survival and progression to ESRD (renal survival) singularly and disease relapse. Kaplan–Meyer survival analysis and multivariate Cox proportional hazard regression analysis were used to explore difference between phenotypes and finding significant predictors regarding outcomes.

Out of 81 patients, 40.7% patients reached primary endpoint, 22.2% died, 29.6% reached ESRD and 16% relapsed during follow-up. Multivariate Cox proportional hazards regression-adjusted analysis found higher BVAS (HR 1.08, 95% CI 1.01–1.17, p = 0.042), higher baseline maximal serum creatinine (HR 1.02, 95% CI 1.01–1.03, p = 0.04) and lower haemoglobin (HR 0.97, 95% CI 0.95–0.99, p = 0.011) significantly associated with primary endpoint. Higher BVAS (HR 1.25, 95% CI 1.01–1.43, p = 0.001) and lower haemoglobin (HR 0.95, 95% CI 0.91–0.99, p = 0.008) were significantly associated with patient survival, while for renal survival, lower haemoglobin (HR 0.97, 95% CI 0.94–0.99, p = 0.041) and the need for acute haemodialysis (HR 3.15, 95% CI 1.20–8.26, p = 0.02) were significant predictors. On multivariate-adjusted analysis, no significant predictors for disease relapse were found. Kaplan–Meier survival analysis found no difference between clinical, serological and pathohistological phenotypes for all of the endpoints.

Renal function at presentation, anaemia and BVAS should be included in prediction models for the outcomes for the AAV patients.