Therapeutic modality of 11 patients with TTP in a single institution in Miyazaki from 2000 to 2011.

Objective: Thrombotic thrombocytopenic purpura (TTP) is a life-threatening generalized disease with pathological features that are termed thrombotic microangiopathies. Since the discovery of the von Willebrand factor-cleaving protease [a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13)], it is widely known that approximately two-thirds of TTP patients have a severe deficiency of ADAMTS13 activity due to gene mutations or acquired autoantibodies to this enzyme. However, the remaining one-third of TTP patients have only moderately reduced or almost normal ADAMTS13 activity.