Interferon-alpha-associated polyarthritis - Possible induction of seropositive rheumatoid arthritis by interferon-alpha: two case reports and review of the literature

We describe a patient with chronic myelogenous leukemia (CML) and a patient with hairy cell leukemia being effectively treated with alpha-interferon w ho developed a seropositive chronic polyarthritis formally fulfilling the A CR criteria for rheumatoid arthritis. Because of its efficacy, interferon w as not discontinued, and the arthritis treated with low-dose prednisolone o r NSAIDS. These are the 19 th and 20 th case of symmetrical polyarthritis d uring alpha-interferon therapy fulfilling the criteria for RA. The possible mechanisms of the relatively frequent appearance of autoimmune diseases du ring interferon therapy are discussed.