The Bottom Line: Thrombotic microangiopathies are microvascular occlusive disorders which are characterized by aggregation of platelets, thrombocytopenia, and mechanical injury to erythrocytes. The clinical distinction between thrombotic thrombocytopenic purpura and the hemolytic–uremic syndrome is not always clear-cut. Microvascular aggregation of platelets occurs in both thrombotic thrombocytopenic purpura and the hemolytic–uremic syndrome. If the aggregation of platelets is systemic, and especially if the central nervous system is involved, the disorder is usually called thrombotic thrombocytopenic purpura. If platelet aggregation is predominantly confined to the renal circulation, the hemolytic–uremic syndrome is often diagnosed. Severe renal involvement in a patient with a diagnosis of thrombotic thrombocytopenic purpura (renal abnormalities occur in 50 to 75 percent of episodes) or extrarenal manifestations in a patient with a diagnosis of the hemolytic–uremic syndrome may erase clinical distinctions between the two entities.
Moake. Thrombotic microangiopathies The New England journal of medicine 2002 vol:347 iss:8 pg:589
TABLE 1.THROMBOTIC MICROANGIOPATHIES page 590
For therapy of TTP, Adults and older children a require daily plasma exchange. If the patient doesn’t respond to plasma exchange alone, treatment with
Glucocorticoids or splenectomy may be considered.