Antiplatelet antibodies in childhood idiopathic thrombocytopenic purpura.

Antiplatelet antibodies were shown by the Handin and Stossel method in the sera of all 103 patients with acute idiopathic thrombocytopenic purpura (ITP) and in 100 cases following recovery from it. These antibodies were also shown in the sera of all 46 patients with chronic ITP and 32 cases after recovery. The decrease in level of antiplatelet antibodies was significant in all these children following recovery (P less than 0.001 for acute ITP, P less than 0.05 for chronic ITP). Antiplatelet antibodies could be determined in 67 acute and 21 chronic ITP cases in thrombocytopenic phase and following recovery, which showed very significant decreases in levels in each case in a later period. Antiplatelet antibody levels corresponding to the thrombocytopenic phase and recovery in acute and chronic ITP were significantly higher than normal and thrombocytopenic control values (P less than 0.001 for each).