Haema 2013; 4(1):47-57
by Theoni Kanellopoulou, Stavroula Giannouli, Dimitrios Pectasides
2nd Department of Internal Medicine and Laboratory, Athens Medical School, General Hospital of Athens Hippokration, Greece
Abstract
Microangiopathic hemolytic anemia accompanies clinical syndromes characterized by thrombotic microangiopathy, thrombocytopenia, and the presence of fragmented red blood cells. Thrombotic thrombocytopenic purpura and hemolytic uremic syndrome are typically characterized by microangiopathic hemolytic anemia and complications from the central nervous system or kidneys respectively. Recent advances in understanding the molecular mechanisms underlying these syndromes not only allow for their pathogenetic classification, but also pave the way for targeted therapeutic approaches. Thrombotic thrombocytopenic purpura is characterized by the presence of antibodies against the metalloproteinase ADAMTS13, while most cases of hemolytic uremic syndrome are triggered by infection with enteropathogenic bacteria secreting Shiga toxins or neuraminidases. However, drugs, malignancies and autoimmune diseases may cause a similar clinical syndrome. Regardless of the underlying etiology, mi- croangiopathic hemolytic anemias are characterized by high mortality and require early diagnosis and prompt therapeutic intervention. Non-immune hemolytic anemias, other than microangiopathic hemolytic anemia, may be due to infections or to exposure to physical injury or toxic factors.