Mechanisms of vWF cleavage by ADAMTS13

TTP and HUS: one disease or a group of distinct disorders?

Thrombotic thrombocytopenic purpura (TTP) typically presents in previously healthy individual with weakness, petechiae, and headache or other neurological abnormalities. TTP and hemolytic-uremic syndrome (HUS), a syndrome encompassing the disease that develops after infection by shiga toxin producing microorganisms and a group of loosely defined atypical disorders, are both characterized by thrombocytopenia and microangiopathic hemolysis. Neurological dysfunction is common in TTP, while advanced renal failure is more typical of HUS. However, the overlapping of manifestations has raised questions on whether TTP and HUS involve the same pathogenetic mechanism. This uncertainty also accounts in part for the common practice of applying plasma exchange in patients with HUS or other types of thrombotic microangiopathy.