Possible involvement of Von Willebrand factor in pancreatic graft thrombosis after kidney-pancreas transplantation: a retrospective study.

Early postoperative graft thrombosis remains the second cause of failure in pancreas transplantation. Thus, the aim of this study was to compare retrospectively coagulation and fibrinolysis in type I diabetic recipients of simultaneous kidney pancreas transplants having or not experienced thrombosis of their pancreatic graft. From December 1990 to August 1996, 30 simultaneous kidney pancreas transplants were performed in 30 uremic type I diabetic patients. Acute thrombosis of the pancreatic graft was observed among 6 patients (group A), whereas 24 did not develop thrombosis (group B) although 4 died from other causes. The control groups were composed of kidney transplant (group C) or haemodialysed (group D) non-diabetic patients, type I diabetics with HbA1C < 8% (group E) or > or = 8% (group F) who were not in end-stage renal failure and kidney transplant type I diabetic patients (group G). Beginning at least 6 months after transplantation, we analysed hemostatic factors (fibrinogen, thrombin, and prothrombin times), coagulation inhibitors (proteins C and S), fibrinolysis (plasminogen activator inhibitor) and endothelial cell abnormalities (Von Willebrand factor: VWf). Micro and macrovascular complications were evaluated on a score ranging from 0 to 12. Hemostatic factors, coagulation inhibitors and fibrinolysis were similar in groups A and B whereas VWf differed significantly in group A (3.49 +/- 0.93 IU/ml) as compared to group B (2.04 +/- 0.92 IU/ml) (p < 0.05). VWf was also significantly increased in group A relative to the control groups C, D, E, F, and G. The score of vascular complications was increased in groups A and B and significantly higher in group A (9 +/- 0.81 vs. 6.07 +/- 1.75) (p < 0.01), while a correlation (r = 0.812, p > 0.05) was observed between VWf levels and the severity of vascular complications. These results point out the possible involvement of VWf in the pathogenesis of pancreatic vein thrombosis in kidney-pancreas transplantation.