[Clinical manifestations of antineutrophil cytoplasmic antibodies associated vasculitis]

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides are rare diseases, with the average of 30 new cases per million inhabitants per year. Their main characteristic is systemic involvement with necrosis of the vessel walls (histological changes showing necrosis of the media and inflammation of adventitia and intima). In some forms granulomas may be found surrounding the vessels. ANCA-associated vasculitides include granulomatosis with polyangiitis (GPA, previously called Wegener's), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (EGPA, previously called Churg-Straus). Honorific eponyms are now changing to a disease-descriptive or etiology-based nomenclature. ANCA-associated vasculitides are a distinctive group of vasculitides because they dominantly involve small sized vessels, sometimes even medium sized vessels, are associated with antineutrophil cytoplasmic antibodies with high risk of developing glomerulonephritis and respond well to immunosuppresion with cyclophosphamide.