Congenital ADAMTS13 deficiency: a rare mimicker of immune thrombocytopenic purpura.

Congenital ADAMTS13 deficiency is a rare disease that leads to recurrent episodes of thrombotic thrombocytopenic purpura. We report a case that mimicked a recurring immune thrombocytopenic purpura in a child. Mild cases of ADAMTS13 deficiency may be initially confused with immune thrombocytopenic purpura if hemolytic anemia is not severe and renal or neurological symptoms are not present. Fresh frozen plasma is the treatment of choice in acute thrombotic thrombocytopenic purpura in ADAMTS13-deficient patients. The best long-term treatment for slightly symptomatic cases remains to be elucidated. Recombinant human ADAMTS13 factor will be a promising option when commercially available.