Thrombotic Microangiopathy

The term thrombotic microangiopathy or TMA represents a broad pathophysiologic process that leads to the development of a microangiopathic hemolytic anemia (MAHA) (characterized by fragmented cells or schistocytes in the peripheral blood) and thrombocytopenia.  The MAHA is a result of a microthrombotic disease that involves the arterioles and capillaries of vascular beds throughout the body.  These widespread microthrombi are the cause of the widespread and varied end organ injury that can be seen in patients diagnosed with a TMA.  The term TMA is also an umbrella term that encompasses many conditions that can present with the characteristic MAHA and thrombocytopenia, but with differing and distinct pathophysiologies and treatment approaches.