RESUMEN
Thromobotic thrombocytopenic purpura-hemolytic uremic syndrome (TTP-HUS), characterized by microangiopathic hemolytic anemia, thrombocytopenia, fever, central nervous system abnormalities, and renal dysfunction, is severe multisystem disorder. TTP-HUS occurs predominantly in the reproductive aged-women, associated with poor prognosis. Although the morbidity and mortality have been significantly decreased by using plasma exchange therapy, refractory TTP-HUS remains a tremendous problem. It is crucial to differentiate other microangiopathic hemolytic anemia disease with a confusing presentation and to perform the immediate plasmapheresis. We have experienced three cases, which were initially diagnosed as HELLP syndrome or immune thrombocytopenic purpura. Despite of aggressive plasmapheresis, two women died. We present these cases with a review of the literature on pregnancy-associated thrombotic microangiopathy, including ADAMTS-13 activity assay as a new diagnostic test.