Eosinophilic granulomatosis with polyangiitis (churg-straus syndrome)

Eosinophilic Granulomatosis with Polyangiitis (EGPA) is defined as an eosinophil-rich and granulomatous inflammation involving the respiratory tract, and necrotizing vasculitis affecting small to medium-sized vessels, and associated with asthma and eosinophilia. It is usually classified among the so-called antineutrophil antibody (ANCA)-associated systemic vasculitides (AASVs) because of its clinical and pathologic features that overlap with those of the other AASVs. However, recent studies on large cohorts of patients have found that ANCA, usually P-ANCA/MPO-ANCA, were present in less than 40 % of patients. Moreover, ANCA status was shown to segregate with clinical phenotype. Preliminary results suggest that ANCA-positive and ANCA-negative patients also might have a different genetic background. Corticosteroids remain the cornerstone of the initial treatment of EGPA. The addition of cyclophosphamide is indicated in patients with poor-prognosis factors or in patients without poor-prognosis factors that relapse early. How long should maintenance therapy be continued remains to be established. However, the vast majority of patients require long-term corticosteroids treatment to control asthma.