Expanded Criteria Donors Allow Successful Expansion On the Donor and Recipient Pools. A Single Centre Experience.

Abstract

Background: Due to the constant increase in waiting lists and the lower disponibility of young donors, the number of transplants from expanded criteria donors is growing continuously. However, their use is still controversial as graft survival could be negatively affected. The aim of the present study was to analyze the donor characteristics that influence graft survival. Patients and methods: It is a retrospective and observational single centre study in which 634 consecutive deceased donor kidney transplants, performed in our Unit between 2000 and 2012 were included. Donor and recipient characteristics and graft outcome were obtained from the electronic medical records. Kidneys from donors with a serum creatinine above 2.5 mg/dl and older than 65 years with more than 25% of glomerulosclerosis in the kidney biopsy were not accepted for transplantation. Results: The mean age of recipients was 52.9±13.0 years, 207 (32.6%) aged more than 60 years. In addition, 67.9% of donors have died by cerebrovascular disease, 46.5 % were more that 60 year old, 35.5% had a previous history of hypertension and 7.7% had a serum creatinine above 1.5 mg/dl. Altogether, 55.0% of grafts came from expanded criteria donors. Furthermore, 61 out of 233 biopsied grafts had >10% of sclerotic glomeruli. As our policy is to transplant old-for-old, there was a significative relationship between recipient and donor age (r=0.691; 95%CI 0.648-0.729;p<0.001). Graft and patient survival at 5 years were 80% and 92% respectively. Cox univariate analysis showed that time on dialysis, donor last serum creatinine, a previous history of donor hypertension and peak PRA were the variables associated with graft survival. In the multivariate analysis; peak PRA (HR:1.01; IC95% 1.00-1.01; p=0.041), donor hypertension (HR:1.86; IC95% 1.27-2.73; p=0.001) and donor serum creatinine (HR 1.20; 95%CI 1.07-1.36;p=0.003) remained in the model. No association was observed between % of donor glomerulosclerosis and graft function at 6 months or survival at 5 years. Conclusions: Our study shows that the use of expanded criteria donors provide satisfactory survival rates and allow increasing the number of transplants. Only donor serum creatinine and a previous history of hypertension but not age were the variables associated with graft survival.