The use of deceased extended criteria donors has shortened wait times for potential transplant reci-pients. Their use has been quite helpful in allowing elderly recipients access to transplant before the onset of intractable complications. Resorting to living extended criteria donation on the other hand represents a total disregard of the interests of the living donor and should be actively discouraged.

Key words : Extended criteria deceased donation, Extended criteria living donation, Standard criteria deceased donation

Introduction

In the early days of transplant, when the only aim was to cure, transplant physicians were very strict in the selection of their donor-recipient pairs. This translated into excellent results. They were quickly able to prove that transplant (1) improves quality of life, (2) prolongs life, and (3) is less expensive than dialysis, in the long term.^1,2

Living donors can only donate a limited number of organs, transplant specialists had to resort to standard criteria deceased donors. The results were not as good but were still very satisfactory. Encouraged by these early successes, transplant specialists started relaxing the contraindications to transplantation, leading to a sharp increase in the number of transplant candidates; however, the demand had rapidly exceeded the offer.

Transplantation Was the Victim of Its Own Success

The donor shortage was made worse by a pathological urge to transplant and a competitive race to achieve the highest donation scores. These developments led to the adoption of a new type of donor: the extended criteria donor (ECD)³; ECDs are suboptimal donors who are older than 60 years of age or older than 50 years of age with 2 of the following comorbidities: serum creatinine above 1.5 mg/dL, uncontrolled hypertension, or death resulting from a stroke.

The kidneys of ECDs are, by definition, kidneys of poorer quality. In general, above the age of 40 years in humans, kidneys start losing 10% of their filtration rate with every decade. Therefore, it is to be expected that kidneys from donors above 50 years of age would show a significant loss of function.^4-6

Old kidneys are more susceptible to injury, have limited repair potentials,^4-9 and are less tolerant to the usual immunosuppressive regimens.¹⁰ The devastating effects of atherosclerosis and hypertension on the kidneys are additive and well-known.¹¹

Kidneys from ECDs also have a higher incidence of graft discard,¹¹ higher incidence of delayed graft function, and an increased risk of postoperative complications, thus leading to decreased graft survival rates.^3,12-14

In an effort to improve these rates, the Kidney Donor Profile Index (KDPI) was introduced. Kidneys from ECDs had to score a KDPI of <20 to match the results of standard criteria deceased donors.^15-17 Only then, with these kidneys could provide better results than chronic dialysis, especially when the kidneys were allotted to a carefully selected group of elderly recipients.¹⁸

The financial benefits of ECD transplantation, on the other hand, became highly questionable in view of the added cost of treatment of complications and the limited years of survival. The number of patients awaiting a second transplant seems to be steadily growing, raising doubts about the efficacy of the use of ECD organs in shortening wait lists.¹⁹

I agree with the specialist in the field insisting that kidney transplantation should have 3 basic aims that constitute the “holy grail” of transplantation: (1) one kidney for life, (2) optimal immunosuppression, and (3) no need for graft biopsies.

Where are we from these aims? I can understand that they are very hard to achieve. Demographic changes have modified the specificities of both donors and recipients. Some countries are forced to rely on older and less ideal donors to fulfill their needs, and recipients are getting older too. It can be argued that older recipients should also be given the opportunity to benefit from the advantages of a successful transplant.

However, for such endeavors to succeed and provide valid results, they should be limited to centers that can provide proper follow-up and have enough expertise, knowledge, and facilities to manage any complications that might emerge. They should also be qualified to draw proper conclusions and present valid corrective plans.

What is really worrisome is that many units around the world are expanding their transplant criteria for the sole purpose of engaging in the race of scoring the highest number of transplants and the highest rates of donations, ignoring or willingly disregarding the quality of their results.

So far, we have been dealing with organs from deceased ECDs. Our only worry, and for obvious reasons, was the well-being of the recipient. In living donation, the problem is quite different.^20,21 This issue should be of particular interest to areas that are served by the Middle East Society for Organ Transplantation where many of our programs rely mainly, if not exclusively, on living donation.²²

With living donors, our main concern should be the protection of the donor. This should preclude the use of living ECDs, except, perhaps, in the case of a highly motivated elderly donor fully aware of the risks incurred and for limited gain expected (eg, a grandfather serving as a bridge to another transplant for his grandchild).

A serum creatinine of 1.5 mg/dL reflects a loss of more than 50% of the glomerular filtration rate. Any additional loss (eg, through unilateral nephrectomy) would inexorably lead to end-stage renal disease.^23-25 It is expected that, when coupled with old age; diabetes, hypertension, and atherosclerosis,²⁶ organ donation would have an even more pronounced adverse effect on renal function.

Our region is characterized by a high rate of consanguineous marriages.²⁷ This is translated into an increased incidence of congenital kidney diseases that could be still latent and difficult to detect in the potential donor. This should stress the importance of a very meticulous work-up before donation.

In 2011, the United Network for Organ Sharing identified 325 “healthy” living donors listed for deceased donor kidney transplant.²⁸ This number is expected to increase with the relaxation of the selection criteria and the adoption of genetically related donors in an often consanguineous population.

If we are not very strict in the selection of our living donors, we should expect to find our waiting lists filled with more so-called “healthy” donors. I strongly believe that an official, close follow-up of the living donor is a must. Before assurance of the safe future of the living donor, however, any steps to engage haphazardly in expanded living donation would be considered criminal. I find it very strange that we insist on subjecting deceased donation to strict rules and regulations while living donation is left to the discretion of transplanting centers.

It is always difficult to turn down a highly motivated donor-recipient pair. It is, however, our duty to guide and protect our patients. Although one can find some justification to the risks involved in the use of organs from deceased ECDs, I strongly believe that donation from living ECDs should be discouraged.

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