Long-term outcome of patients with ANCA-associated vasculitis treated with plasma exchange: a retrospective, single-centre study

Plasma exchange (PLEX) has been used routinely for treatment of severe renal vasculitis and/or alveolar haemorrhage (AH) in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), but the long-term benefit of PLEX in AAV remains unclear. We aimed to describe the characteristics and outcomes of patients treated with PLEX in a single centre.

Patients with AAV were identified by performing a case review of medical records of 705 patients who received PLEX in a single tertiary referral centre between 2000 and 2010. Patient characteristics and outcomes were recorded. The Kaplan-Meier method, log-rank tests and Cox regression analysis were used for survival analyses.

A total of 94 patients with AAV were identified (44 men, 50 women; median age 60 years, range 21–90 years; 52 proteinase 3-ANCA, 41 myeloperoxidase-ANCA and 1 ANCA-negative; 8 double-positive for ANCA and anti-glomerular basement membrane; 93 newly diagnosed/1 relapse; 55 [58.5 %] required dialysis). The reasons for initiating PLEX therapy were severe renal involvement alone in 52 %, AH in 10 %, both renal involvement and AH in 35 %, and “other” in 3 %. The patients had 3–27 (median 7) PLEX sessions. At 3 months, 81 (86 %) of 94 were alive and 62 (66 %) of 94 were alive and dialysis-independent. The median follow-up was 41 months (minimum-maximum 0.5–137 months), when 56 (59.6 %) of 94 patients were alive and 47 (50 %) were dialysis-independent. The estimated overall survival rates were 75.3 % at 1 year and 61.1 % at 5 years. Patient survival decreased with increasing age at presentation (5-year survival 85 % for age <50 years, 64.4 % for ages 50–65 years, and 41 % for >65 years; p < 0.01 for comparison between all groups). Estimated renal survival rates were 65.5 % at 1 year and 43 % at 5 years. Renal survival was worse in patients aged >65 years than in the younger patients (5-year survival 25.1 % in patients >65 years vs. 50.8 % for those ≤65 years, p < 0.01). The estimated renal survival was better in patients with higher Disease Extent Index (DEI) >6 than in patients with DEI ≤6 (5-year survival 52.1 % vs. 39.4 %, p = 0.04), even though this was not confirmed in multivariate analysis.

The mortality of patients presenting with severe manifestations of AAV remains high despite the use of PLEX. Older age at presentation is associated with worse overall and renal prognosis.