Use of Expanded Criteria Donors Gives Significantly Poorer Long-Term Graft Survival

Abstract

Introduction: The use of expanded criteria donor (ECD) kidneys remains controversial as various groups have reported conflicting outcomes in terms of long-term graft outcomes. It is however well-known that ECD kidneys afford shorter graft survival as compared to kidneys from a standard criteria donor (SCD). In Singapore, patients with end stage renal failure (ESRF) must meet strict medical criteria before they are allowed to be placed on the National Transplant Registry to await a deceased donor kidney, including the absence of clinically overt cardiovascular and cerebrovascular disease. The aim of this study was to determine if there is a difference in long-term graft survival between recipients of SCD and ECD kidneys. Methods: A retrospective review was conducted on all deceased donor renal transplants (DDRT) performed at the Singapore General Hospital from 1st January 2000 to 31 December 2010. Results: During this period, 272 adults underwent a DDRT, with 226 (58.7%) receiving an SCD kidney (Group 1), and 46 (12.0%) receiving an ECD kidney (Group 2). The etiology of ESRF was predominantly chronic glomerulonephritis in both groups (83.1% Group 1 vs 73.9% Group 2, p = 0.75). The mean dialysis duration pretransplant was similar in both groups (45.3+8.7 vs. 46.7+9.0 months in Groups 1 and 2 respectively, p=0.28). While an increased incidence of early acute rejection (a rejection episode within 3 months post-transplant), and delayed graft function (a need for dialysis within a week post-transplant), are risk factors for decreased long-term graft function, the incidence of both events was similar in both groups (10.2% vs. 19.6%, p=0.07, and 42.5% vs. 54.4%, p=0.14, in Groups 1 and 2 respectively). Graft survival at 1 year was similar in both groups (96.0% Group 1 and 91.3% Group 2), but at 5 years there was a clear difference in graft survival (97.1% Group 1 and 68.4% Group 2). The 10-year graft survival was significantly reduced in recipients of ECD kidneys (p< 0.001) (Figure 1). Long term graft survival as described by half-lives was less than 6 years for ECD grafts and more than 10years for SCD grafts.[Figure 1]Conclusion: Patients receiving ECD kidneys, regardless of whether they have experienced an early acute rejection episode or delayed graft function, have a significantly reduced long-term graft survival. This is despite being in similar health as SCD recipients, with the absence of clinically overt cardiovascular and cerebrovascular disease pre-transplant. The use of ECD kidneys should be considered only in selected recipients.