Granulomatous vasculitis.

Granulomatous vasculitis is a subset of systemic necrotizing vasculitis and has granulomatous inflammation as the main histopathologic feature. Etiopathogenesis remains poorly understood, although recent advances suggest an important role for certain pro-inflammatory cytokines, such as tumor necrosis factor-alpha. They are a heterogeneous group of clinical disorders with protean manifestations. Serologic abnormalities are present, and the presence of granular cytoplasmic staining-antineutrophil cytoplasmic antibodies is most important and is particularly useful for the diagnosis of active Wegener's granulomatosis. Corticosteroids and cyclophosphamide remain very useful in the treatment of most of these disorders.