What is thrombotic microangiopathy?

TMA is clinically revealed by a hemolytic uremic syndrome (HUS). Causes: ➢ So-called "typical" HUS (postdiarrheal, especially in children): infection with enterobacteria producing "shiga-like toxins": E. Coli O157H7 ++; ➢Thrombocytopenic Thrombotic purpura; ➢ Drugs (cyclosporine, gemcitabine, quinine, etc.); ➢ HUS complicating an underlying disease : malignant hypertension, antiphospholipid syndrome, scleroderma, cancers; ➢ HELLP syndrome during pregnancy; ➢ Genetic origin: anomaly in the genes encoding the regulatory proteins of the alternate complement pathway (so-called “atypical” HUS). ➢ The initial lesion is endothelial, causing platelet aggregation and the formation of fibrino-platelet thrombi