Vascular thrombosis after kidney transplantation: predisposing factors and risk index.

Early graft thrombosis is an uncommon complication, but the vast majority of cases are unrecoverable. The aims of this study were to assess the variables involved in the development of this complication and to create a prognostic index to define which transplants, by virtue of a combination of variables, show a higher risk of thrombosis. We retrospectively analyzed a cohort of 577 cadaveric renal transplants performed between 1992 and 2009, excluding those with hypercoagulability before transplantation. The overall incidence of thrombosis was 6%. The distribution of thrombosis was examined according to recipient variables, differences in dialysis within 24 hours before transplantation (0 no dialysis, 13.8% dialysis out of hospital, and 4.2% dialysis in hospital; P=.029) and iliac vascular pathology (10% yes vs 5% no; P<.04). The donor-related factors were age above or below 60 years (11% vs 5%; P=.01), stroke versus traumatic death cause (9.3% vs 4.7%; P=.049), and graft atheroma (16.7% yes vs 5.1% no; P=.042). Immunotherapeutic factors were tacrolimus versus cyclosporine (7.4% vs 2.3%; P=.001) and use of sequential therapy (10.7% yes vs 3.3% no; P=.001). The odds ratio (OR) of thrombosis for the use of basiliximab adjusted for donor age, recipient age, and graft atheroma was 2.6 (95% CI, 1.03 to 6.63). Upon multivariate analysis, the predictive equation consisted of: stroke donor death, OR 3.88; recipient iliac vascular pathology, OR 2.81; and graft atheroma, OR 3.63. The predictive validity by receiver operating characteristic curve provided an area of 0.769 (95% CI, 0.67 to 0.87; P<.0001). The thrombosis risk index suggested that transplantation into a recipient with iliac vascular pathology, stroke as the cause of donor death, and graft atheroma multiplied the risk by 16 compared with a standard recipient without iliac vascular pathology with a traumatic cause of donor death, and without graft atheroma.