Antibody subtypes and titers predict clinical outcomes in ANCA-associated vasculitis

The objective of this study is to evaluate the association between antineutrophil cytoplasmic autoantibody (ANCA) subtype and ANCA titers on clinical outcomes and disease activity among a cohort of patients from Central Appalachia diagnosed with ANCA-associated vasculitis (AAV) over a 3-decade period. This is a retrospective chart review of all patients diagnosed with AAV. ANCA subtypes (myeloperoxidase (MPO) and proteinase 3 (PR3)) and titers at the time of diagnosis and at the time of relapse or last follow-up were evaluated along with patient outcomes. Outcomes of interest included relapse, development of end-stage renal disease (ESRD) and mortality. Sensitivity analysis and multivariable analysis were performed. Of the 202 patients, 111 patients were MPO-ANCA positive and 91 patients were PR3-ANCA positive. Relapse was more frequent among patients with PR3-ANCA compared to MPO-ANCA (35% vs 12%,p <  0.001). In both ANCA subgroups, the strongest predictor of relapse was an increase in titers prior to relapse, HR 8.1 (95% CI 1.6–40),p 0.009. Patients who achieved serological remission had a lower risk of ESRD [sub-HR 0.31 (95% CI 0.11 –0.89)] and mortality [HR (95% CI) 0.24 (0.07–0.7)]. PR3-ANCA was associated with higher risk of ESRD [sub-HR 3.1 (95% CI 1.1–8.5)]. There was no difference in mortality between patients with MPO-ANCA and PR3-ANCA. Our study supports the use of both ANCA subtypes and titer levels for predictin g clinical outcomes in patients rece...
Source: Rheumatology International - Category: Rheumatology Source Type: research