Comparison of Expanded Criteria Kidneys With 2-Tier Standard Criteria Kidneys: Role of Delayed Graft Function in Short-Term Graft Outcome Faissal Abdulraheem Shaheen, 1 Besher Attar, 2 Fayez Hejaili, 3 Saleh Binsalih, 3, 4 Abdulla Al Sayyari 5 Abstract Objectives: To compare transplant outcomes between expanded criteria donor kidneys and standard criteria donor kidneys. Materials and Methods: All adult renal transplants from deceased donors performed in Saudi Arabia over a 24-month period were included. Donor and recipient factors were recorded, and their effects on outcomes with expanded criteria donor and standard criteria donor kidneys were compared. Standard criteria donor kidneys were further subgrouped into optimal and suboptimal groups, and outcomes were compared. Results: A total of 280 deceased-donor kidney transplants were performed during the study period. Of these, 61 (21.8%) involved expanded criteria donor kidneys. Cold ischemia time and prevalence of delayed graft function were similar between expanded criteria and standard criteria kidneys (P = .7 and P = .8). Graft survival rates at 2 years were also similar (93.3% vs 94.6%; P = .8). Delayed graft function exerted a negative effect on 2-year graft survival in both the expanded group (hazard ratio, 4.9; 95% CI 3.2-7.5; P = .001) and the standard group (hazard ratio, 4.6; 95% CI 3.24-7.5; P = .001). No difference was found between the 2 standard criteria subgroups with respect to serum creatinine value at the end of follow-up (P = .8), delayed graft function prevalence (P =.5), or 2-year graft survival (P = .8). The only independent factor affecting graft survival was delayed graft function (P = .001). No independent effect was seen for expanded criteria donor versus standard criteria donor, donor serum creatinine level, or recipient age. Conclusions: Similar short-term outcomes were found for expanded criteria and standard criteria kidney recipients. Delayed graft function was associated with significant risk of graft loss in both groups, with decreases in 2-year graft survival of 33.3% and 18.3%. No difference was seen between the 2 subtypes of standard criteria donor kidneys. Key words: Cyclosporin, Tacrolimus, mTOR, Renal transplant, Adverse effects Introduction A deceased-donor kidney is classified as an expanded criteria donor (ECD) kidney if the donor is ≥ 60 years of age or is 50 to 59 years of age with at least 2 of the following 3 medical criteria: serum creatinine (SCr) level > 132.6 μmol/L (> 1.5 mg/mL), history of hypertension, or cardiovascular accident as the cause of death. 1 All kidneys that do not meet these criteria are considered standard criteria donor (SCD) kidneys. With the use of Cox regression analysis, ECD criteria were developed to specifically identify deceased-donor kidneys with a relative risk of graft loss of 1.7 compared to SCD kidneys. 2 One factor in the recent increase and wide acceptance and use of ECD kidneys has been the severe shortage of SCD kidneys combined with the relatively large proportion of ECD kidneys to the Copyright © Başkent University 2012 Printed in Turkey. All Rights Reserved. 1 Director-General, Saudi Centre for Organ Transplantation; 2 Consultant Nephrologist, Head of Medical Section, Saudi Centre for Organ Transplantation; 3 Associate Professor of Medicine, King Saud Bin Abdulaziz University for Health Sciences; 4 Chairman, Department of Medicine, King Abdulaziz Medical City, and 5 Professor of Medicine, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia Conflict of interest: None declared Address reprint requests to: Professor Abdulla Al Sayyari, Professor of Medicine, King Saud Bin Abdulaziz University for Health Sciences, POP Box 22490, Riyadh 11426, Saudi Arabia Phone: +966 1 2520088 84 Fax: +966 1 2520088 Ext 14229 E-mail: aaalsayyari@gmail.com Experimental and Clinical Transplantation (2012) 1: 18-23 ArtIcle DOI: 10.6002/ect.2011.0147