**Abstract**

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) constitute a group of necrotizing systemic vasculitis with preferential involvement of small- to medium-sized vessels. None treated; they are considered as a life-threatening illness by their renal, cardiac and neurologic damages. Therefore, treatment is usually aggressive, with high-dose corticosteroid therapy combined with immunosuppressive drugs in the major part of cases. New biologic drugs have been introduced such as rituximab. In this chapter, we will present the update and recent advances in the treatment of AAV.

**Keywords:** ANCA vasculitis, granulomatosis with polyangiitis (Wegener's), microscopic polyangiitis, Eosinophilic granulomatous with polyangiitis, treatment

## **1. Introduction**

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) constitute a group of necrotizing systemic vasculitis with preferential involvement of small- to medium-sized vessels. They represent serious disorders, and three clinical subtypes are involved: granulomatosis with polyangiitis (GPA; formerly Wegener's disease), microscopic polyangiitis (MPA) and eosinophilic GPA (EGPA; formerly Churg Strauss Syndrome). They share similar pathogenic mechanisms, and most patients have only one ANCA serotype detected in their serum [1, 2]. Non-treated, they were considered as fatal or life-threatening illnesses. In the last two decades, better knowledge of pathogenic mechanisms and progression in classification criteria improved therapeutic management [3–5]. Treatment is usually aggressive, with high-dose corticosteroid therapy combined with immunosuppressive drugs in the major part of cases. New biologic drugs have been introduced such as rituximab [4]. In this chapter, we will present the update and recent advances in the treatment of AAV.
