Antineutrophil cytoplasmic autoantibody-associated vasculitis in Chinese patients.

Antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) is a common autoimmune disease in China. AAVs in the majority of Chinese patients are microscopic polyangiitis with antigenicity to myeloperoxidase. Propylthiouracil is the leading cause of drug-induced AAV. The genetic background and immunological characteristics of ANCA, such as the epitope, IgG subclass and avidity, might contribute to various clinical phenotypes of AAV.