Behavior of ADAMTS13 and Von Willebrand factor levels in patients after living donor liver transplantation.

Background: Thrombotic microangiopathy (TMA) is one of the important complications occurring after liver transplantation (LT), and it is suggested that a Von Willebrand factor (VWF) and ADAMTS13 may play an important role in the onset of TMA and poor outcome after LT.

Methods: In 81 patients after living donor LT (LDLT), 17 patients who had both severe thrombocytopenia and hemolytic anemia with fragmented red cell were diagnosed as TMA- like syndrome (TMALS) and 10 patients died.

Results: ADAMTS13 activities were slightly low, and plasma levels of VWF and VWF propeptide (VWFpp) antigens and the ratio of VWFpp/VWF were significantly high before LDLT. ADAMTS13 activities were significantly reduced from day 1 to day 28 after surgery, and plasma levels of VWF antigen slightly decreased on day 1 and plasma levels of VWFpp continued to be high. The ratio of VWFpp/VWF was significantly high on day 1 after surgery. The mortality was high in the patients with TMALS and the frequency of TMALS was high in non-survivors. VWF levels were significantly low and the ratio of VWFpp/VWF was significantly high in those with TMALS on day 1 after surgery. The ADAMTS13 activity was significantly low, and the VWFpp and the VWFpp/ADAMTS13 ratio were significantly high in non-survivor on day 28 after surgery.

Conclusions: These findings suggest that VWF and ADAMTS13 might therefore play an important role in the onset of TMA and poor outcome after LT. The VWFpp may therefore be a more useful marker for the diagnosis of TMALS than VWF.