Churg-Strauss syndrome (Ch-S) is a rare disease with such characteristic features as necrotizing eosinophilic vasculitis with accompanying bronchial asthma and peripheral blood eosinophilia. Treatment includes  application of corticosteroids as  well as other immunosuppressive drugs such as cyclophosphamide and azatioprine.

Interferon-α (IFN-α) – a cytokine with a strong antiviral effect is effectively applied in treatment of viral hepatitis B and C as well as in treatment of hypereosinophilic syndromes, including Ch-S. IFN-α in the dose of 3 million units 3 times in a week was applied as additional treatment over 16 weeks in 2 patients with confirmed diagnosis of Ch-S.

IFN-α treatment caused a quick improvement of patients’ health, manifested by an increase of FEV1, decrease of peripheral blood eosinophilia and reduction of dose of prednisone. During treatment slight side effects typical for IFN-α were observed. Addition of IFN-α to treatment does not cause full control of the disease; a thorough monitoring of health state is required to determine the optimal dose of prednisone.