TY - CHAP M1 - Book, Section TI - Thrombotic Thrombocytopenic Purpura A1 - Hardin, J. Matthew A2 - Knoop, Kevin J. A2 - Stack, Lawrence B. A2 - Storrow, Alan B. A2 - Thurman, R. Jason Y1 - 2021 N1 - T2 - The Atlas of Emergency Medicine, 5e AB - Thrombotic thrombocytopenic purpura (TTP) was previously defined by the following pentad of symptoms: (1) microangiopathic hemolytic anemia, (2) thrombocytopenia, (3) renal abnormalities, (4) fever, and (5) neurologic abnormalities. However, at initial presentation, only 10% of acute TTP patients have all of these symptoms. Most TTP patients will have severe thrombocytopenia (usually < 30,000/mm3), microangiopathic hemolytic anemia (schistocytes in the blood smear), and a constellation of clinical findings (petechia, purpura, neurologic symptoms, myocardial ischemia, mesenteric ischemia, and renal abnormalities). Approximately 50% of TTP presentations have an associated comorbidity that may trigger the disease (autoimmune diseases, antiphospholipid syndrome, pregnancy, medications, HIV infection, pancreatitis, malignancy, and organ transplantation), whereas the other 50% are idiopathic. SN - PB - McGraw-Hill CY - New York, NY Y2 - 2024/03/28 UR - accessemergencymedicine.mhmedical.com/content.aspx?aid=1181043807 ER -