An acute or subacute syndrome characterized by the presence of microangiopathic hemolytic anemia, thrombocytopenic purpura, fever, renal abnormalities and neurologic abnormalities such as seizures, hemiplegia, and visual disturbances. Drugs and bacteria have been implicated as etiologic factors. The introduction of plasma exchange has significantly lowered the mortality rate. If untreated, the mortality rate is high. Check for "https://www.cancer.gov/about-cancer/treatment/clinical-trials/intervention/C78797" active clinical trials using this agent. ("http://ncit.nci.nih.gov/ncitbrowser/ConceptReport.jsp?dictionary=NCI%20Thesaurus&code=C78797" NCI Thesaurus)