Using rheopheresis for stem cell transplantation-associated thrombotic microangiopathy (TA-TMA).

Stem cell Transplantation-Associated Thrombotic Microangiopathy (TA-TMA) is an awful complication with high morbidity and mortality. The reported incidence varies from 0.5% to 75% due to the difficulty of diagnosis in these patients. They do not respond to plasma exchange and despite new treatments, such as defibrotide and rituximab, mortality rate ranges between 60% and 90%. Rheopheresis is a specific application of membrane differential filtration for extracorporeal hemorheotherapy that has been used in the diabetic foot syndrome, venous leg ulcer, pulmonary hypertension, sudden hearing loss, macula degeneration and peripheral arterial occlusive disease. The main therapeutic basis of Rheopheresis is the reduction of blood and plasma viscosity that results in improvements of microcirculation and blood flow. The physiopathologic mechanism associated with TA-TMA is the loss of endothelial cell integrity with hypercoagulability secondary to infections, immunosuppressive therapy and graft-versus-host disease. Because of this, we believe that treatment with Rheoapheresis may improve microcirculation and resolve TA-TMA. We report two patients diagnosed of severe TA-MA successfully treated with Rheopheresis using a selective fibrinogen adsorption system (Rheosorb) with a LIFE-18 apheresis unit (Miltenyi Biotec), an integrated plasma therapy instrument.