Thrombotic microangiopathy (TMA) is a broad pathophysiologic process that leads to microangiopathic hemolytic anemia and thrombocytopenia, and involves capillary and small-vessel platelet aggregates. The most common cause is disseminated intravascular coagulation, which may be differentiated by abnormal coagulation. Clinically, a number of conditions present with microangiopathic hemolytic anemia and thrombocytopenia, including cancer, infection, transplantation, drug use, autoimmune disease, and pre-eclampsia and hemolysis, elevated liver enzymes and low platelet count syndrome in pregnancy.
Lab tests
• ADAMTS13:
to assist in diagnosis of thrombotic thrombocytopenic purpura (TTP) and in distinguishing between inherited and acquired forms of TTP.
If ADAMTS13 activity is ≤30%, then ADAMTS13 inhibitor will be added; if ADAMTS13 inhibitor is <0.7 BU, then ADAMTS13 antibody will be added.
• ADAMTS13 activity
• ADAMTS13 Inhibitor: If suspicion for TTP remains after a negative result, ADAMTS13 antibody is recommended.
• ADAMTS13 Antibody
Reference
- Scully M, Cataland S, Coppo P, de la Rubia J, Friedman KD, Kremer Hovinga J, et al. Consensus on the standardization of terminology in thrombotic thrombocytopenic purpura and related thrombotic microangiopathies. Journal of thrombosis and haemostasis: JTH. 2017;15(2):312-22.
- Go RS, Winters JL, Leung N, Murray DL, Willrich MA, Abraham RS, Amer H, Hogan WJ, Marshall AL, Sethi S, Tran CL, Chen D, Pruthi RK, Ashrani AA, Fervenza FC, Cramer CH, Rodriguez V, Wolanskyj AP, Thomé SD, Hook C, Mayo Clinic Complement Alternative Pathway-Thrombotic Microangiopathy Disease-Oriented Group. Thrombotic Microangiopathy Care Pathway: A Consensus Statement for the Mayo Clinic Complement Alternative Pathway-Thrombotic Microangiopathy (CAP-TMA) Disease-Oriented Group. Mayo Clin Proc. 2016; 91(9): 1189-211. PubMed
