Eosinophilic Granulomatosis with Polyangiitis (Churg-Strauss)

Eosinophilic granulomatosis with polyangiitis (EGPA), formerly called Churg-Strauss syndrome, is a systemic necrotizing vasculitis of small- and medium-size vessels, characterized by asthma and blood eosinophilia. EGPA typically occurs in patients with preexisting asthma, and involves the skin, lungs, and peripheral nerves. Poor-prognosis factors (i.e., involvement(s) of the gastrointestinal tract, heart, and/or kidney) have been assessed with the Five-Factor Score (FFS). One-third of the patients have anti-myeloperoxidase antineutrophil cytoplasm antibodies, and their presence seems to differentiate between two phenotypes, with different clinical characteristics and prognoses. Overall survival has improved markedly since the use of glucocorticoids and immunosuppressants, but relapse rates remain high. All patients require glucocorticoids, and for those with severe/refractory disease and FFS-defined poor prognoses, immunosuppressants should be used (cyclophosphamide for induction and azathioprine for maintenance therapy). Recent advances in EGPA management, including several novel immunomodulatory drugs and targeted biotherapies, were or are being evaluated to improve EGPA patients' prognoses.