RT Book, Section A1 Lichtman, Marshall A. A1 Kaushansky, Kenneth A1 Kipps, Thomas J. A1 Prchal, Josef T. A1 Levi, Marcel M. SR Print(0) ID 1126655019 T1 Antibody-Mediated Thrombotic Disorders: Thrombotic Thrombocytopenic Purpura and Heparin-Induced Thrombocytopenia T2 Williams Manual of Hematology, 8e YR 2011 FD 2011 PB McGraw-Hill Education PP New York, NY SN 9780071622424 LK hemonc.mhmedical.com/content.aspx?aid=1126655019 RD 2024/03/28 AB Thrombotic microangiopathies are characterized by thrombocytopenia, microangiopathic hemolytic anemia, and microvascular thrombosis, leading to variable injury of the central nervous system, kidney, and other organs.The classic form of thrombotic microangiopathy, i.e., thrombotic thrombocytopenic purpura (TTP) is usually associated with an acquired (autoimmune) deficiency of ADAMTS13, a metalloprotease that cleaves ultralarge multimers of von Willebrand factor.Hemolytic uremic syndrome (HUS) refers to the thrombotic microangiopathy that mainly affects the kidney and may be diarrhea-associated (caused by enteric infection with Shiga-toxin producing gram-negative microorganisms) or atypical.Secondary thrombotic microangiopathies occur in association with infections, certain drugs, metastatic cancer, malignant hypertension, or after stem cell transplantation.Heparin-induced thrombocytopenia (HIT) is a significant complication of heparin treatment, associated with mild to moderate thrombocytopenia and a high frequency of both arterial and venous thrombosis. HIT is caused by the formation of anti-heparin/platelet factor-4 antibodies that activate platelets, leukocytes and endothelial cells.