POS0255 IMPACT OF PLASMA EXCHANGE (PLEX) IN SEVERE ANCA-ASSOCIATED VASCULITIS (AAV): A REAL-LIFE DATA FROM A PROSPECTIVE COHORT
Authors: E. Bilgin, E. Duran, E. Erkantarci Levent, T. Yildirim, M. Arici, A. İ. Ertenli, O. Karadag
Journal: Annals of the Rheumatic Diseases (2021)

Background: PEXIVAS was the largest clinical trial conducted on severe AAV patients and failed to demonstrate the contribution of PLEX on the prognosis of severe AAV. This data needs to be tested with real life experiences. Objectives: The aim of this study was to explore the effects of PLEX on the prognosis of severe AAV in a real-life cohort. Methods: Hacettepe University Vasculitis Research Center (HUVAC) prospective database was established in October 2014 by registering past and newly diagnosed patients. Baseline disease characteristics, treatments and survival status were recorded. For this study, patients with granulomatosis polyangiitis (GPA) and microscopic polyangiitis (MPA) who met the inclusion criteria of PEXIVAS trial [briefly; ANCA positive MPA or GPA patients with either severe renal involvement (necrotizing glomerulonephritis or active urinary sediment, and eGFR &lt;50 ml/min) and/or severe pulmonary involvement (pulmonary hemorrhage due to active vasculitis)] at the disease onset were included. Patients were grouped whether they had PLEX or not. Demographic and disease-specific data and immunosuppressive agents used in induction phase were compared. Primary outcome was accepted as composite index of mortality or end-stage renal disease (ESRD) at the first year and at the final visit. Results: Of 145 GPA and MPA patients, 49 patients had inclusion criteria and distribution of patients were as GPA (n=38), MPA (n=8) or renal-limited (n=3). 16 (32.6%) patients had PLEX. Median number of plasma exchange cycles was 6.5 (min-max; 2-12). Although severe pulmonary [10 (62.5%) vs. 5 (15.2%), p=0.001] and combined severe renal+pulmonary involvements were more prevalent [9 (56.3%) vs. 4 (12.1%), p=0.001] and baseline creatinine levels were higher in PLEX (+) group, BVAS and FFS scores were similar (Table 1). Induction immunosuppressive regimens were comparable. At first year evaluation, primary composite outcome was observed in 11 patients (3 deceased, 8 ESRD) of PLEX (+) group whereas in 12 patients (2 deceased, 10 ESRD) of PLEX (-) group (p = 0.03, log-rank). In multivariate analysis: combined renal+pulmonary involvements (aOR: 6.5 [1.1-37.9]) and serum creatinine (for 1 mg/dl increment) (aOR: 1.3 [1.1-1.7]) were associated with primary outcome. In this model, having plasma exchange was not associated with a favorable outcome. At the end of median follow-up [40.7 (1.2-170.3) months], outcome was observed in 12 patients (9 deceased, 3 ESRD) of PLEX (+) group and in 13 patients (6 deceased, 7 ESRD) of PLEX (-) group (p &lt; 0.001, log-rank). In multivariate analysis: having plasma exchange (HR: 3.5 [1.4-8.5]) and combined renal+pulmonary involvements (HR: 2.4 [1.05-5.8]) were found as the predictors of primary composite outcome. In the figure 1, comparison of primary outcome according to FFS and plasma exchange status was given. Conclusion: In real-life plasma exchange did not have a positive impact on the composite index of mortality and ESRD, similar to PEXIVAS trial. Presence of combined severe renal and pulmonary involvement was the predictor of worse outcome at 1-year and overall follow-up. Table 1. Comparison of disease characteristics and composite indexes of patients PLEX (+ ) (n=16 ) PLEX (-) (n=33 ) GPA/MPA/Renal-limited (n) 12/3/1 26/5/2 Female, n(%) 8 (50.0) 13 (39.4) Age at diagnosis, months (med,min-max) 54.5 (18.8-77.8) 55.6 (18.1-86.3) MPO-ANCA / PR3-ANCA (n) 5 / 11 16 / 17 Follow-up duration, months (med, min-max) 16.6 (1.2-116.5) 50.5 (2.2-170.0) BVAS at diagnosis, (med, min-max) 23 (14-37) 23 (8-33) FFS ≥ 2 (n,%) (N=45) 23 (85.7) 26 (83.9) Creatinine (mg/dl) at diagnosis † (med,min-max) 8.1 (4.1-8.9) 3.1 (1.8-6.2) CRP (mg/dl) at diagnosis (med,min-max) 21.8 (15.0-29.0) 11.5 (3.6-20.0) Immunosuppressive (induction) (n,%) - Pulse steroid 14 (87.5) 29 (87.9) - Rituximab 1 (6.3) 3 (9.1) - Cyclophosphamide 12 (75.0) 28 (84.8) † p = 0.005 Figure 1. Comparison of primary outcome according to FFS and plasma exchange status Disclosure of Interests: None declared