Endothelial Markers: Thrombomodulin and Von Willebrand Factor and Risk of Kidney Thrombosis After Transplantation

Objective. Endothelial disturbance is well known as one of the causes of thrombosis. This study measured von Willebrand factor (vWF) and soluble thrombomodulin (sTM) in renal vein blood to evaluate for the risk of thrombosis after kidney transplantation. Methods. A cross-sectional study that included 61 consecutive recipients of kidney transplant. The sTM and activity of vWF were evaluated in blood of the renal vein at the time of reperfusion. Results. The renal vein blood had higher values of vWF activity and sTM concentration than the peripheral blood. In the first minutes of reperfusion, the concentration of thrombomodulin was the highest but activity of vWF was the lowest. As the reperfusion continued, thrombomodulin gradually decreased, but vWF increased. The strong correlations of TMs and vWF with warm ischemia were observed (r = 0.5577 and r = 0.3429, respectively). Thrombosis was found in about 10% of all recipients. However, other complications, such as delayed graft function or ureter necrosis, were associated with high values of vWF and sTM. They were correlated with increased sTM concentration and activity of vWF (P <.006 and P <.05, respectively). This was confirmed by analysis of the receiver operator characteristic curve. The area under the curve values for TMs and vWF were 0.762 and 0.602, respectively (P <.0001 and P <.015, respectively). The cutoff points for sTM and vWF were 14.89 ng/mL and 129.89%, respectively. Positive prediction value sTM and vWF were 76% and 66% and negative prediction value 69% and 59%, respectively. Conclusions. The endothelium of a transplanted kidney could be involved in the pathogenesis of renal thrombosis. Endothelial protection during harvesting can greatly contribute to the improvement of transplantation outcomes. The renal pool of sTM and vWF could be a useful marker of the risk of renal thrombosis.

Automated summary

This study indicates that measuring the concentrations of vWF and sTM in renal vein blood can evaluate the risk of thrombosis after kidney transplantation. High values of vWF and sTM are associated with complications such as delayed graft function or ureter necrosis, and are significantly correlated with the rate of thrombosis.