0041-1337/00/6902-281/0 TRANSPLANTATION Vol. 69, 281–285, No. 2, January 27, 2000 Copyright © 2000 by Lippincott Williams & Wilkins, Inc. Printed in U.S.A. OUTCOME IN RECIPIENTS OF DUAL KIDNEY TRANSPLANTS AN ANALYSIS OF THE DUAL REGISTRY PATIENTS 1 AMY D. LU, 2 JONATHAN T. CARTER, 2 REBECCA J. WEINSTEIN, 2 ROBERT J. STRATTA, 3 RODNEY J. TAYLOR, 4 VICTOR D. BOWERS, 5 LLOYD E. RATNER, 6 KENNETH D. CHAVIN, 6 , LYNT B. JOHNSON, 7 PAUL C. KUO, 7 EDWARD H. COLE, 8 DONALD C. DAFOE, 2 AND EDWARD J. ALFREY 2,9 Department of Surgery, Stanford University, Stanford, California; Department of Surgery, University of Tennessee, Memphis, Tennessee; Department of Surgery, University of Nebraska, Omaha, Nebraska; Lifelink Transplantation Institute, Tampa, Florida; Department of Surgery, Johns Hopkins University, Baltimore, Maryland; Department of Surgery, Georgetown University, Washington, D.C., and Department of Medicine, University of Toronto, Toronto, Ontario, Canada Background. A novel but controversial method to increase the utilization of aged donor kidneys is the transplantation of both kidneys as a dual transplant. Initial single-center reports demonstrated outcomes similar to single kidneys from younger donors. In this report, we compare outcome in recipients of kidneys from donors >54 years of age who received a single kidney transplant reported to the United Network for Organ Sharing Scientific Registry versus a dual kid- ney transplant reported to the Dual Kidney Registry. Methods. A retrospective analysis was performed, comparing four donor and nine recipient and outcome variables between recipients of a single versus a dual transplant between March 1993 and March 1999. Results. Dual versus single transplants from donors >54 years of age have a significantly decreased inci- dence of delayed graft function, and lower serum cre- atinines up to 2 years after transplant despite having kidneys from significantly older donors with poorer HLA matching. Conclusions. Dual kidney transplants improve graft performance and outcome in recipients of kidneys from donors >54 years of age. In 1998, for the first time in 3 years, there was a substan- tial increase in cadaveric donors (1). Older donors accounted for the largest of the overall 5.6% increase reported by the United Network for Organ Sharing (UNOS). Donors above the age of 60 years increased by 10.7%, and donors age 40 –59 years increased by 9.6%. Although the use of older donors for kidney transplantation does increase the absolute number of transplants performed, there are several reports showing decreased graft performance and outcome in recipients of kidneys from older donors (2–16). The use of dual kidney transplantation was developed as a method to expand the utilization of aged donor kidneys from expanded criteria donors (ECDs*) that would have otherwise been discarded. Preliminary reports of dual transplants have shown favorable early outcomes, comparable to that of recip- ients of kidneys from younger donors (17, 18). Initial studies demonstrated an improvement in the incidence of delayed graft function (DGF), decreased rejection episodes, with graft and patient survival equal to that of single cadaveric renal transplants from younger donors. In an attempt to better understand appropriate utilization of these kidneys, a Dual Kidney Registry was developed to follow patients from mul- tiple centers. The centers participating in the dual registry have demonstrated an interest in the aggressive pursuit of dual kidney transplantation. In this report, we evaluate do- nor and recipient variables, and outcome from the Dual Kid- ney Registry in recipients of dual transplants from donors 54 years of age. We compare the group of dual recipients with the UNOS Scientific Registry for recipients of single kidneys from donors 54 years of age. PATIENTS AND METHODS The Dual Kidney Registry is administered at Stanford University and includes patients from seven centers who received dual renal transplants between March 1993 and March 1999. At the time of this analysis, there were 121 patients enrolled in the database, an aver- age of 17 per center. Of these, there were 84 recipients of dual kidneys from donors 54 years of age. The remaining patients re- ceived dual transplants from donors 54 years of age. The 84 dual transplant patients were compared to recipients of single trans- plants from the UNOS database (n=4803) transplanted between January 1994 and December 1997 from donors 54 years of age. Donor data evaluated included age, any history of hypertension, terminal creatinine, and calculated terminal creatinine clearance (C Cr ) using the Cockcroft-Gault equation (19). This method of deter- mining C Cr has validity in hospitalized patients (20, 21). Recipient data included age, HLA match, incidence of DGF (dialysis in the first week after transplant), serum creatinine at 6 months and 1, 2, and 3 years, graft loss during the study period, and 1- and 3-year actuarial graft survival. Data was entered into a relational database. The unpaired t test, or chi-square was performed accordingly. Signifi- cance was defined at P0.05. Analyses were also made after recipi- ents of dual and single kidneys were grouped based upon recipient 1 Presented in abstract form at the 25th Annual Meeting of the American Society of Transplant Surgeons, May 19 –21, 1999, Chi- cago, IL. 2 Department of Surgery, Stanford University. 3 Department of Surgery, University of Tennessee. 4 Department of Surgery, University of Nebraska. 5 Lifelink Transplantation Institute. 6 Department of Surgery, Johns Hopkins University. 7 Department of Surgery, Georgetown University. 8 Department of Medicine, University of Toronto. 9 Address correspondence to: Edward J. Alfrey, M.D., Department of Surgery, MSOBx338, Stanford University, Stanford, CA 94305. E-mail: ealfrey@leland.stanford.edu. * Abbreviations: C Cr , creatinine clearance; DGF, delayed graft function; ECD, expanded criteria donor; UNOS, United Network for Organ Sharing. 281