Plasma exchange in the treatment of fulminant idiopathic (autoimmune) thrombocytopenic purpura.

Rapid plasma exchange in a young man with idiopathic (autoimmune) thrombocytopenic purpura and life-threatening haemorrhage acutely increased the platelet-count and enhanced haemostasis. The patient had not responded to steroids, and massive intra-abdominal bleeding had developed after splenectomy, despite numerous platelet transfusions. After plasma exchange, his haemoglobin concentration became normal without further transfusion and his abdominal girth decreased. Therefore emergency reoperation because of intra-abdominal bleeding was no longer required. A cumulative-sums plot of his platelet-count confirmed that plasmapheresis on 2 occasions was followed by a pronounced rise in mean platelet-count. Neither prednisone nor vincristine therapy altered the slope of the plot. The high initial anti-platelet antibody concentration in this patient fell after plasma exchange. These findings indicate that plasmapheresis accelerated clearance of circulating anti-platelet factors in fulminant idiopathic thrombocytopenic purpura.