Thrombotic Microangiopathy in Living-Donor Liver Transplantation

Abstract

Thrombotic microangiopathy (TMA) is a fatal complication characterized by microvascular occlusive disorder resulting in systemic or intrarenal platelet aggregation, severe thrombocytopenia, and microangiopathic hemolytic anemia. Only sporadic case reports of TMA after cadaveric or living-donor liver transplantation (LDLT) have been described. The authors report 10 (5% of the total series) TMA patients after LDLT and review the previously reported cases. TMA was diagnosed on the basis of progressive thrombocytopenia of unknown cause and microangiopathic hemolytic anemia, suggested by sharp elevation of serum lactate dehydrogenase levels and the presence of fractionated erythrocytes in blood smear. Of the 10 patients with TMA, 7 presented with viral hepatitis (2 with hepatitis B and 5 with hepatitis C virus infection) as the cause of end-stage liver disease. Clinical diagnosis of TMA was made at a median interval of 18 days (range, 3-356 days) from the time of transplantation. Conversion of calcineurin inhibitors (CNI) was conducted in nine patients. One patient recovered after CNI conversion alone. Plasma exchange was performed in eight patients. Three patients died. Immediate treatment of TMA should be initiated by reduction or conversion of CNI followed by plasma exchange. Hepatitis C virus infection might contribute to the high incidence of TMA in LDLT patients.