ANCA vasculitis - figuring out who really needs maintenance therapy

This is a study for patients with anti-neutrophil cytoplasmic antibody (ANCA) vasculitis who are in remission after treatment. We want to learn if a special blood test can help us identify which patients could be monitored without additional immunosuppressive maintenance treatment. This study will not test new medications. We will use the same medications currently used for maintenance treatment of ANCA vasculitis.