Prognosis of chronic thrombocytopenic purpura.

A multicenter prospective study on the treatment of chronic idiopathic thrombocytopenic purpura (ITP), conducted by the Idiopathic Disorders of Hematopoietic Organ Research Committee, the Ministry of Health and Welfare of Japan, is currently in progress. In this study we analyzed the clinical records of 256 patients with chronic ITP in order to define the prognostic factors. As of November, 1988 after a median observation period of 34 months, 174 of the 256 patients (68%) were alive, 11 (4%) dead and 71 (28%) lost to follow-up. Bleeding was a direct cause of death in only one patient. Assessment of the status of patients based on platelet count at the final observation revealed that 48% of patients were in remission, 21% showed improvement, and 31% remained unchanged or worsened. Univariate analyses identified 4 parameters associated with favorable prognosis: presenting platelet count less than 2 x 10(4)/microliters, platelet count greater than 10 X 10(4)/microliters after one-year follow-up, maximal platelet count greater than 10 X 10(4)/microliters during administration of the initial dose of corticosteroids and splenectomy.