[Long-term maintenance of platelets by IFN alpha-2b in a case of chronic idiopathic thrombocytopenic purpura refractory to prednisolone therapy].

A 63-year-old female with chronic idiopathic thrombocytopenic purpura refractory to prednisolone therapy was treated with interferon alpha-2b (IFN alpha-2b). Initially, the patient received 2 courses of short-course therapy in which 1.5 million IU and IFN alpha-2b was subcutaneously injected 3 times a week every other day for 4 weeks. During the first course, the platelet count rose from 1.0 x 10(4)/microliters to 12.4 x 10(4)/microliters 3 weeks after the beginning of the therapy, but the effect was transient. In the second course the platelet-increasing effect was lower than that in the first course. Then, intermittent injections of 3 million IU of IFN alpha-2b once a week were subsequently begun. Consequently, the patient's platelet count has been maintained at 5 to 9 x 10(4)/microliters for more than 19 months since the beginning of intermittent IFN alpha-2b therapy.