BACKGROUND: In the treatment of adult patients with idiopathic thrombocytopenic purpura(ITP), prednisone is the initial therapy. Splenectomy is the treatment of choice in patient who are refractory to prednisone therapy and reported overall response rate to splenectomy is about 50 to 80%. We reviewed the long-term response to splenectomy and attempted to find any factors predicting which patient would have a good response.
METHODS: We studied retrospectively 39 patients with chronic ITP who had first been treated with prednisone alone or with prednisone and immune globulin and then undergone splenectomy. The response to the treatment was classified on the basis of the platelet count as no response (<50,000/micro L), incomplete response
(50,000~150,000/micro L), or complete response (>150,000/micro L). The response was evaluated within 2 weeks after splenectomy (immediate response) and during follow-up period (follow-up response).
RESULTS: The median age of patients was 30 (range: 18~72) and the ratio of male to female was 13:26. Immediately after splenectomy, complete response was obtained by 30 patients while 6 had incomplete response and in 3 patients splenectomy failed. Among 39 patients, follow-up evaluation was obtained in 32 patients. During the follow-up period (mean duration of follow-up was 23 months), 9 patients relapsed after splenectomy and the sustained response (continued complete or incomplete response for more than 3 months without any treatment) was observed in 62.5% of the patients. Postsplenectomy thrombocytosis was an early feature of durable response. Among 39 patients, intravenous immune globulin was administered in 28 patients before splenectomy, and response to immune globulin was also a favorable factor to sustain the response.
CONCLUSION: Patients who do not have responses to intravenous immune globulin may still respond to splenectomy initially, but are unlikely to sustain response for a long time.

Keywords: ITP, Splenectomy, Immune Globulin, Response, Prognostic Factor