This type of thrombotic microangiopathy more commonly resembles the he
molytic-uremic syndrome (HUS) than thrombotic thrombocytopenic purpura
(TTP). The syndrome has been associated with the use of cyclosporin,
mitomycin C, combinations of other chemotherapeutic and immunosuppress
ive agents, and total body irradiation. Endothelial cell injury and vo
n Willebrand factor may be involved in pathogenesis of the intravascul
ar platelet aggregation and tissue (especially renal) ischemia and inf
arction that characterize the entity. The most effective therapy for t
hrombotic microangiopathy associated with drugs and bone marrow transp
lantation has not been determined.