High-Dose Intravenous Immune Globulin and the Response to Splenectomy in Patients with Idiopathic Thrombocytopenic Purpura

BACKGROUND: High-dose intravenous immune globulin produces a temporary rise in the platelet count in patients with idiopathic thrombocytopenic purpura. Splenectomy may also be effective, but it is not possible to predict which patients will have a good response. We hypothesized that the response to intravenous immune globulin predicts the response to splenectomy. METHODS: We studied retrospectively 30 patients with idiopathic thrombocytopenic purpura who had first been treated with immune globulin and then undergone splenectomy. The responses to the two treatments were classified on the basis of the platelet count as poor (<50,000 per cubic millimeter), good (50,000 to 150,000 per cubic millimeter), or excellent (>150,000 per cubic millimeter). RESULTS: All nine patients who had poor responses to intravenous immune globulin also had poor responses to splenectomy at one year. Of the 21 patients with good or excellent responses to intravenous immune globulin, 19 had good or excellent responses to splenectomy. CONCLUSIONS: Patients with idiopathic thrombocytopenic purpura who have good or excellent responses to intravenous immune globulin are likely to have good or excellent responses to splenectomy, whereas patients who have poor responses to intravenous immune globulin are unlikely to have good or excellent responses to splenectomy.