Proposal of categorization of expanded criteria donors in renal transplantation

Transplantation of renal allografts that have been procured from expanded criteria donors (ECD) have prevailed in an attempt to expand the donor pool. Even though ECD is an acceptable source of donors, the wide range of age along with the presence or not of risk factors necessitates further categorization. The aim of this study was to analyze the allograft and recipient survival of the ECD renal grafts and to propose an ECD categorization model.

We reviewed the medical records of renal transplant recipients from January 2002 to July 2012, who received renal allografts from expanded and standard criteria donors (SCD) without risk factors such as hypertension, cerebrovascular disease or impaired renal function.

During the study period, 310 renal transplantations were performed in our Transplant Unit, of which 86 and 114 renal grafts were procured from ECD and SCD respectively. ECD renal graft survival the first, third and fifth year was 92%, 82% and 70% while respective recipient survival was 95%, 87% and 82%. Comparison with the control group of SCD showed that ECD renal graft survival after the third post-transplant year was significantly inferior (P < .0001). Donor age was a considerable prognostic factor of long-term renal graft function. Serum creatinine of ECD grafts was the first and third year 1.86 ± 0.6 mg/dL and 1.91 ± 0.8 mg/dL, respectively, showing significant difference to that of SCD grafts (P < .0001). Further categorization of ECD showed that renal allografts procured from donors above 60 years old without risk factors had better renal graft survival and function compared to grafts procured from donors aged 50-59 with 2 or 3 risk factors.

Renal transplantation from ECD offers acceptable graft survival rates, however they are inferior compared to renal grafts from optimal kidney donors. ECD kidney grafts have to be categorized, taking into consideration the independent risk factors.