Thrombotic thrombocytopenic purpura in early pregnancy.

Thrombotic thrombocytopenic purpura during pregnancy in which both mother and fetus have survived has been an exceedingly rare occurrence, due at least in part to the difficulty in distinguishing this uncommon disease from hematologic complications of preeclampsia. In the nonpregnant patient, the use of plasma infusion or exchange plasmapheresis as therapy of choice has resulted in a dramatic increase in survival. By using more specific criteria than the classical clinical pentad, the diagnosis of thrombotic thrombocytopenic purpura during pregnancy can be made with greater accuracy. The first known instance of the successful use of exchange plasmapheresis leading to the survival of both mother and fetus in thrombotic thrombocytopenic purpura clearly not secondary to preeclampsia is reported.