#1399 The prognostic significance of the Birmingham Vasculitis Activity Score on the outcome of ANCA- associated vasculitis

Abstract Background and Aims Anti-neutrophil cytoplasmic antibody (ANCA) -associated vasculitis (AAV) is related to substantial morbidity and mortality, even with the latest treatments. Renal involvement is common in AAV and the most important mortality predictor. The Birmingham Vasculitis Activity Score (BVAS) has emerged as an essential tool in assessing disease activity and predicting long-term prognosis. The study evaluated the association between BVAS and outcomes in renal vasculitis patients. Method A retrospective study was carried out from 2021 to 2024. Twenty patients (13 women and 7 men) with systemic vasculitis were included in the study. Clinical and laboratory data were collected. The BVAS was evaluated for all the patients. Patients were divided into three groups according to their outcomes: remission, renal replacement therapy (RRT), and nonsurvivors. Results Eight patients had the presence of PR3- ANCA and twelve patients were positive for MPO-ANCA. All patients were presented with impaired renal function. Nine patients made renal remission, three patients needed RRT, and eight patients did not survive. The BVAS ranged from 6 to 22 (mean 13.2 ± 3.6). The mean BVAS in the remission group was 10.89 ± 2.89, in the RRT group 13.00 ± 1.73, and in the nonsurvivors 15.88 ± 3.18. Independent Kruskal- Walli's test showed a significant relationship between groups χ²(2) = 8.724, P = 0.013, but without specifying among which groups. After the Bonferroni adjustment, a significant difference between BVAS in the remission group and nonsurvivors was found, χ²(2) = 8.444, P = 0.009, and no difference between remission and RRT groups, and RRT and nonsurvivors was found. Conclusion These findings indicate that BVAS might be a prognostic indicator of ANCA-associated vasculitis. Moreover, BVAS can contribute to the early identification of high-risk patients requiring more aggressive therapeutic interventions. However, further investigation would be necessary to confirm this hypothesis.