Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

**Semantic type:** Disease or Syndrome

**Definition:** A group of rare autoimmune disorders characterized by small-to-medium vessel vasculitis and the presence of anti-neutrophil cytoplasmic autoantibodies (ANCA). Some cases may be associated with infection or the use of certain medications.

**Synonyms:** - AAV - ANCA-Associated Vasculitis - Antineutrophil Cytoplasmic Autoantibody-Associated Vasculitis - Antineutrophilic Cytoplasmic Antibody-Associated Vasculitis