LAUSR

Background The antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) are rare multisystem autoimmune diseases of unknown cause, characterised by inflammatory cell infiltration causing necrosis of blood vessels. The AAV comprise granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (EGPA). The AAV are autoimmune diseases with potentially severe systemic involvement that require prolonged immunosuppressive therapy. Infection is a frequent complication in AAV and is associated with increased morbidity and mortality. Objectives The aim of this study was to define epidemiology, ANCA patterns, treatments, infections and outcomes of a series of 39 patients with AAV. Methods We retrospectively analysed 39 patients diagnosed with AAV between 1995 and 2017 from the Internal Medicine Department of a Spanish referral centre. Results A total of 39 patients were reviewed. 23 female (58.9%). Mean age at diagnosis was 55.6 years. Median time delay to diagnosis was 7.6 weeks. Median follow-up was 91.3 months. Most frequent AAV was MPA with 18 patients (46.2%), followed by GPA with 11 (28.2%) and EGPA with 10 (25.6%). 6 patients (15.4%) had a concomitant autoimmune disease: Systemic sclerosis,2 Antiphospholipid syndrome,2 Lupus1 and Sjögren.1 Only 2 patients (5.1%) had previous infection with hepatitis C virus. Regarding the treatments, all patients received corticoids (bolus 24 patients, 61.5%), 29 (74.4%) cyclophosphamide, 10 (25.6%) rituximab, 19 (48.7%) azathioprine, 4 (10.3%) mycophenolate and 1 (2.6%) methotrexate. 16 patients presented post-treatment lymphopenia, 5 pancytopenia, and 15 hypogammaglobulinemia. 21 patients (53.8%) presented any infection after the diagnosis. The most frequent were bacterial infections (15 patients), presenting 9 patients with sepsis criteria (7 due to gram-negative organisms). 9 opportunistic infections were described: 3 infections by cytomegalovirus, 5 by tuberculosis and 1 by Mycobacterium avium. There were no cases of Pneumocystis jirovecii despite the fact that only 16 patients (41%) performed primary prophylaxis. The factors associated with increased risk of infections were: lymphopenia, pancytopenia and increased BVAS (p<0.05). 6 patients had died at the time of the study (3 associated with infections, 2 with neoplasms and 1 directly with AAV). The Charlson index performed at the time of the study was the best predictor of mortality (p<0’01). Conclusions Infections were a frequent complication in patients with AAV and one of the main causes of mortality. Risk factors were lymphopenia, pancytopenia and increased BVAS. Bacterial infections were the most frequent but opportunistic infections must be taken into account. Reference [1] Kronbichler A, Jayne DR, Mayer G. Frequency, risk factors and prophylaxis of infection in ANCA-associated vasculitis. Eur J Clin Invest. 2015Mar;45(3):346–68. Disclosure of Interest None declared