[Immunoglobulins in Hematology. Immunologic thrombopenic purpura]

Immunologic thrombopenic purpura refers to several diseases including the most frequent, autoimmune thrombopenic purpura (AITP). Immunologic thrombopenia is related to anti-platelet autoantibodies, usually IgGs. In 15 to 20% of the cases, no auto-antibody can be detected. The severity of the cutaneomucosal manifestations is not always correlated with the degree of thrombopenia but only occurs for platelet counts less than 50 x 10(9)/L. The clinical course includes acute episodes of AITP and complete remissions in 80% of the cases in the episodes of AITP and complete remissions in 80% of the cases in the very young child. Inversely, in the adult, treatment of AITP has been highly debated because chronicity is frequent. Two therapeutic approaches, corticotherapy and splenectomy, have been widely used. Corticoids given at a dose of 0.5 to 1 mg/kg/day leads to remission in 15 to 30% of the cases. Splenectomy, a second intention therapy, leads to platelet counts above 100 x 10(9)/L in 60 to 70% of the patients. In 1981, intravenous polyvalent immunoglobulins were first employed for 13 children in a study reported by Imbach et al. The results have been confirmed in children and in adults. There are few side effects with this method and the dose of 1 g/kg over 2 days is effective. Response is rapid (platelet counts above 50 x 10(9)/L in 1 to 5 days) but often temporary (relapse to former levels in 5 to 45 days). The high cost of this intravenous polyvalent immunoglobulins has led to much debate over their use.(ABSTRACT TRUNCATED AT 250 WORDS)