[Thrombotic thrombocytopenic purpura in a newborn].

We report the case of a newborn presenting with hemolytic anemia, thrombocytopenia, hyperbilirubinemia, and renal failure in the first hours of life. An early plasmatherapy was undertaken, with good outcome. The specific von Willebrand factor-cleaving protease activity (ADAMTS 13 for a disintegrin and metalloprotease with thrombospondin type 1 repeats) was found to be low. This is the specific biologic diagnostic element of congenital thrombotic thrombocytopenic purpura (TTP). This disease of constitutional thrombotic microangiopathy is rare. The prognosis, usually life-threatening, was completely transformed given the better understanding of the pathogenesis of the disease and therapeutic progress.