Postoperative thrombotic thrombocytopenic purpura in an infant: case report and literature review.

Thrombotic thrombocytopenic purpura is caused by an imbalance of von Willebrand factor and its cleaving protease, which leads to the formation of microthrombi in end-organs. It rarely occurs in the pediatric population. Plasma exchange can significantly reduce mortality and morbidity. We present a 14-month-old infant in whom clinical and laboratory abnormalities compatible with thrombotic thrombocytopenic purpura were noted several days after resection of a large pelvic tumor. Treatment with double volume plasma exchange on postoperative day 5 led to complete resolution of the renal failure, thrombocytopenia, anemia, and neurological manifestations. ADAMTS13 inhibitors were negative and no mutations were found in factor H, factor I, membrane cofactor protein, and thrombomodulin to account for genetic predisposition to thrombotic thrombocytopenic purpura or atypical hemolytic uremic syndrome. Postoperative anemia, thrombocytopenia, fever, and neurological deficits in children should raise the suspicion of thrombotic thrombocytopenic purpura. Early diagnosis is important because the disorder is readily and efficiently treated with plasma exchange.