[Autoimmune hemolytic anemia reactivated by alpha-interferon therapy in a case of chronic active C-type hepatitis].

A case with autoimmune hemolytic anemia (AIHA) induced by interferon-alpha (IFN-alpha) is presented. A 40-year-old male who had a previous history of autoimmune hemolytic anemia, agranulocytosis and thrombocytopenia was admitted to our hospital because of chronic C type hepatitis. Liver biopsy was performed, which diagnosed chronic active hepatitis and IFN-alpha was administrated at a dose of 3 Meg unit per day. 11 days after the initiation of the therapy he developed hemolytic anemia, but Coombs tests were negative. Although IFN was withdrawn 15 days later, anemia became progressively more serious. 20 days later, both direct and indirect Coombs tests became positive. He was diagnosed as AIHA and treated with methylprednisolone pulse therapy, then he recovered soon afterward. Further analysis of Coombs tests revealed that he had both cold type and warm type (IgG) autoantibodies which was the same type of antibodies for AIHA he suffered 10 years ago. In conclusion, latent AIHA may be reactivated by the treatment with IFN-alpha.