Relapses in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis: a retrospective study

Objective To investigate the activity of relapsing events (RE) and their mode of presentation in patients with anti-neutrophil cytoplasmic (ANCA)-associated vasculitis (AAV). Methods Patients diagnosed with AAV between 1990 and 2015 experiencing at least one RE were investigated. The different organ involvements were registered during each RE. Presentation at initial onset (IO) and RE were compared. The Birmingham Vasculitis Activity Score was used to assess the activity. Results Ninety-nine patients were followed: 54 patients with 96 RE and 45 patients with none. The rate of RE was 53% with a median time of follow-up of 6.8 years. The mean time to first RE was 2.8 years. Thirty patients experienced one single RE, 15 had 2, 5 had 3, 2 had 4, and 2 had, respectively, 7 and 8. Fifty-five percent of RE had the same features as IO. Compared to IO, some clinical manifestations were less present: constitutional symptoms (29% vs 69%), ear-nose-throat (50% vs 76%), lung involvement (59% vs 76%), peripheral neuropathies (14% vs 24%), arthritis (7% vs 27%), kidney (25% vs 41%), and heart (4% vs 20%) (p < 0.001). Skin, eye, and bowel manifestations were not significantly less involved during RE. The mean Birmingham Vasculitis Activity Score at IO was 9.02 and 5.11 at relapse (p < 0.0001). Among the 96 RE, 46% had a new organ involvement compared to IO: none were life-threatening. Conclusion Global activity of RE in AAV patients is lower than that of IO. Fewer organs are involved in relapses. RE turned out to begin with the same manifestations as IO in most cases.center dot First study looking into clinical characteristics of relapses including mostly granulomatosis with polyangiitis.center dot Around half of patients with AAV seemed to relapse in a similar way compared to the initial diagnosis.center dot The activity score during relapsing events is less important.