Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare systemic disease that can be classified as both hypereosinophilic condition and an antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis characterized by granulomatous inflammation. The pathogenesis of EGPA not completely understood. It likely this Th2-mediated, blood tissue eosinophilia serves the main diagnostic criteri...

Before the mid-1980s the only autoantibody widely used to assist in diagnosing vasculitic disease was IgG antibody to the alpha(3) domain of the noncollagenous part of type IV collagen (anti-glomerular basement membrane). Since that time, antineutrophil cytoplasmic antibodies (ANCAs) directed at the azurophilic granule proteins proteinase-3 and myeloperoxidase have been established as clinicall...