Granulomatosis with Polyangiitis (Wegener's)

Granulomatosis with polyangiitis (Wegener's) (GPA (WG)) is a rare autoimmune disease that affects tissue parenchyma and vessels. Although considered a form of small and medium-sized vessel vasculitis, vascular injury is not a feature of all lesions. While the airways and kidneys have long been considered "signature" sites of disease, any organ can be affected. Antineutrophil cytoplasmic antibodies (ANCA) are likely to have a role in pathogenesis, but disease may occur in its absence. Treatment has vastly changed over the past 40 years. Chronic long-term cyclophosphamide therapy is rarely necessary and discouraged. Morbidity and mortality have been dramatically reduced. Opportunistic infections remain common adverse events and are the leading cause of deaths within the first year of illness. Without a better understanding of etiology, cures will be unlikely, and chronic therapy is usually required.