tanahashi yoshinao

Purpose: The main causes of thrombocytopenia with liver disease remain unclear. The aim of this study was to clarify intervention of ADAMTS-13 for thrombocytopenia. Materials and Methods: We reviewed 14 children in which living donor liver transplantation was performed from June 2004 to August 2006 in our hospital. Perioperative platelet count ADAMTS-13 activity and von Willebrand factor (VWF) activity were measured and correlation with various factors was reviewed. Results: The platelet count on the second postoperative day (POD2) was significantly lower than preoperatively but it recovered two weeks later. Dominant factors correlating with the lower platelet count on POD2 were preoperative platelet count, recipient's age, PELD (Pediatric End-stage Liver Disease) score and GRWR (graft vs. recipient weight ratio). Postoperative recovery rate of platelet (POD7/POD2 platelet count) was 1.27 ± 0.47 but all ABO-incompatible cases were below 1. ADAMTS-13 activity was measured in 7 cases. ADAMTS-13 activity on POD7 was significantly lower than preoperatively (p=0.045) and showed positive correlation with prothrombin time on POD7. ADAMTS-13 activity on POD7 in the case of a recovery rate of platelet<1 was significantly lower than in the case that of≧1 (p=0.025). ADAMTS-13 activity showed negative correlation with vWF activity and positive correlation with platelet count in the case of a recovery rate of platelet<1. Conclusions: Preoperative ADAMTS-13 activity suggested progression of liver disease and postoperative activity reflected a graft function. The decrease of ADAMTS-13 activity may be a cause of thrombocytopenia after liver transplantation.