Eosinophilic granulomatosis with polyangiitis: understanding the disease and its management.

Eosinophilic granulomatosis with polyangiitis is characterized by asthma, blood and tissue eosinophilia and small-vessel vasculitis. The clinical presentation is variable, but two main clinic-pathologic subsets can be distinguished: one hallmarked by positive ANCA and predominant 'vasculitic' manifestations (e.g. glomerulonephritis, purpura and mononeuritis multiplex) and the other by negative ANCA and prominent 'eosinophilic' manifestations (e.g. lung infiltrates and cardiomyopathy). The pathogenesis is not fully understood but probably results from the interplay between T and B cells and eosinophils. Eosinophilic granulomatosis with polyangiitis must be differentiated from several conditions, including hypereosinophilic syndromes and other small-vessel vasculitides. The overall survival is good; however, patients frequently relapse and have persistent symptoms. The recently developed monoclonal antibodies targeting B cells and eosinophilopoietic cytokines such as IL-5 are emerging as valid alternatives to conventional immunosuppressive therapies. In this review, we discuss the essential features of eosinophilic granulomatosis with polyangiitis, with particular respect to the most relevant issues concerning clinical presentation and management.