Optimizing Allocation of Kidneys from Older Donors

To the Editor: In a recent issue of the American Journal of Transplantation, Ekser et al. (1Ekser B Furian L Broggiato A et al.Technical aspects of unilateral dual kidney transplantation from expanded criteria donors: Experience of 100 patients.Am J Transplant. 2010; 10: 2000-2007Abstract Full Text Full Text PDF PubMed Scopus (71) Google Scholar) reported excellent 3-year patient and graft survival in 173 recipients of single or dual kidney transplants from donors older than 60 years. Kidneys from donors older than 70 years or from younger donors with at least one predefined comorbidity were used for dual or single transplantation according to the histological score at baseline biopsy, whereas those from donors between 60 and 69 years without comorbidities were transplanted singularly. Dual grafting procedures were done with unilateral placement of both kidneys, which reduced operating time and surgical trauma compared to classical bilateral anastomosis. Importantly, outcomes of recipients of dual or single grafts from donors older than 60 years were similar and actually comparable to those reported for recipients of younger kidneys. The above findings confirm and extend results of a prospective, matched cohort study we run in cooperation with three Renal Transplant Centers in Italy and the Nord Italia Transplant network (2Remuzzi G Cravedi P Perna A et al.Long-term outcome of renal transplantation from older donors.N Engl J Med. 2006; 354: 343-352Crossref PubMed Scopus (415) Google Scholar), showing that 2-year survival of kidneys from donors older than 60 years allocated to single or dual transplantation according to the preimplantation biopsy score was similar to that of younger kidneys from ideal donors and exceeded by 20% the survival of older kidneys transplanted as single without a pretransplant histologic evaluation. Excellent outcomes were observed even with kidneys from donors older than 70 years (3Rigotti P Ekser B Furian L et al.Outcomes of renal transplantation from from very old donors.N Engl J Med. 2009; 360: 1464-1465Crossref PubMed Scopus (28) Google Scholar). Thus, available data consistently show that biopsy-guided selection and allocation of kidneys from older donors is a reliable and efficient strategy to prolong graft survival while expanding the donor pool—by approximately 25% at our Institution (4Ruggenenti P Dimitrov BD Remuzzi G Long-term outcome of renal transplantation from older donors. Authors reply.N Engl J Med. 2006; 354: 2071-2074Crossref Google Scholar). A mathematical modeling of our findings (2Remuzzi G Cravedi P Perna A et al.Long-term outcome of renal transplantation from older donors.N Engl J Med. 2006; 354: 343-352Crossref PubMed Scopus (415) Google Scholar) also indicated that for 100 patients on a waiting list, at 10 years there will be three deaths among recipients of grafts that have undergone histologic evaluation and 11 deaths among recipients of grafts that have not undergone histologic evaluation (4Ruggenenti P Dimitrov BD Remuzzi G Long-term outcome of renal transplantation from older donors. Authors reply.N Engl J Med. 2006; 354: 2071-2074Crossref Google Scholar). At the same time, the numbers of patients who are predicted to be alive with a functioning kidney are similar in the two groups (45 and 43, respectively). These data definitely challenge the statements in the Shapiro et al. editorial that ‘we lack precise criteria to guide clinicians’ to the single or dual transplant procedure because ‘histology may have poor predictive value and is not easy to assess’ (5Shapiro R Halloran PF Delmonico FL Bromberg JS The ‘Two, one, zero’ decision: What to do with suboptimal deceased donor kidneys.Am J Transplant. 2010; 10: 1959-1960Abstract Full Text Full Text PDF PubMed Scopus (31) Google Scholar), and extend the evidence that the biopsy-guided approach is an efficient and reliable strategy to maximize the success of transplantation with older donors (1Ekser B Furian L Broggiato A et al.Technical aspects of unilateral dual kidney transplantation from expanded criteria donors: Experience of 100 patients.Am J Transplant. 2010; 10: 2000-2007Abstract Full Text Full Text PDF PubMed Scopus (71) Google Scholar, 2Remuzzi G Cravedi P Perna A et al.Long-term outcome of renal transplantation from older donors.N Engl J Med. 2006; 354: 343-352Crossref PubMed Scopus (415) Google Scholar, 3Rigotti P Ekser B Furian L et al.Outcomes of renal transplantation from from very old donors.N Engl J Med. 2009; 360: 1464-1465Crossref PubMed Scopus (28) Google Scholar, 4Ruggenenti P Dimitrov BD Remuzzi G Long-term outcome of renal transplantation from older donors. Authors reply.N Engl J Med. 2006; 354: 2071-2074Crossref Google Scholar,6Remuzzi G Grinyò J Ruggenenti P et al.Early experience with dual kidney transplantation in adults using expanded donor criteria. Double Kidney Transplant Group (DKG).J Am Soc Nephrol. 1999; 10: 2591-2598Crossref PubMed Google Scholar). Studies will help assessing whether the performance of this approach can be further enhanced by combined evaluation of other variables, such as donor renal function at recovery or renal resistive indexes at pulsatile machine perfusion (7Delmonico FL Burdick JF Maximizing the success of transplantation with kidneys from older donors.N Engl J Med. 2006; 354: 411-413Crossref PubMed Scopus (25) Google Scholar). Identification of new biomarkers might also provide additional information on expected graft outcomes. This will hopefully enhance the opportunities for successful transplantation for patients older than 50 years of age—a group currently numbering about 50 000 in the United States (8US Department of Health and Human Services. Organ Procurement and Transplantation Network. Available at http://optn.transplant.hrsa.gov/latestData/rptData.asp (accessed on September 27, 2010)Google Scholar). The authors of this manuscript have no conflicts of interest to disclose as described by the American Journal of Transplantation.