An Overview of Living Kidney Transplantation
Living donation occurs when a living person decides to donate one of their kidneys to someone in need of a transplant. This is referred to as a directed donation since the donor specifies the recipient. When donors decide to donate to anyone who needs a kidney transplant, this is commonly referred to as an altruistic or non-directed donation. They do not specify who should receive their kidney.
Donating a kidney is the most frequent type of living organ donation and living kidney transplants have the highest success rate of all transplant procedures. Other organs which can be donated via living donation include liver, lung, small bowel and pancreas.
Being born with one kidney is not unusual. About 1 in every 750 people is born with just one kidney and the life expectancy is the same as those with two kidneys.
Who Can Donate a Kidney?
A living kidney donation often comes from a family member (i.e. a parent, child, sibling or other relative). A donor can also be a spouse, friend or co-worker. Or it can be a stranger. A genetic link between donor and recipient, although beneficial, is not necessarily required. This is largely due to improved anti-rejection medications. These type of “non related” transplants are becoming more common.
A good living donor candidate is someone who is healthy, well-informed and makes a voluntary decision to donate one of their kidneys. Living donors must be over 18 and usually under 70 years of age. They must be in good general health with no evidence of significant high blood pressure, diabetes, cancer, kidney disease, heart disease or hepatitis.
Several tests are necessary to determine if the donor’s’ kidney will be compatible for the intended recipient.
The Different Types of Living Kidney Transplants are:
Related
Related living donors are healthy blood relatives of transplant candidates. They can be:
- parents
- siblings
- children over 18 years of age
- other blood relatives (aunts, uncles, cousins, half brothers and sisters, nieces and nephews)
Non-Related
Unrelated living donors are healthy individuals emotionally close but not related by blood to transplant candidates. They can be:
- spouses
- in-law relatives
- close friends
- co-workers, neighbors or other acquaintances
Non-Directed (Altruistic)
Non-directed donors are living donors who are not related to or known by the recipient and make their donation purely out of selfless motives. This type of donation is also referred to as anonymous, altruistic, altruistic stranger, or stranger-to-stranger living donation.
Individuals who are interested in becoming non-directed donors should contact transplant centers in their area to discuss the possibility of becoming a donor.
Paired Kidney Exchange Programs
Paired kidney exchanges are becoming very common and an exciting option for kidney recipient and donor pairs who are not compatible with each other. Previously, people with kidney failure who had an incompatible donor were not able to benefit from the transplant being offered to them. However, paired kidney exchange programs are having a significant impact on the expanding options of living kidney transplants. Paired exchanges are now allowing transplants to occur between incompatible donor pairs and in a few unique ways.
How Does a Paired Kidney Exchange Work?
A paired exchange consists of two or more donor/recipient pairs who are not compatible with each other. Paired kidney exchanges are a major breakthrough in living donations and are revolutionizing living donor transplants by eliminating incompatibility as a barrier to donation and providing a way for recipients and their incompatible donor to be paired with another incompatible recipient and donor.
In Pair 1, Donor 1 is not compatible with Recipient 1. In Pair 2, Donor 2 is not compatible with Recipient 2. However, Donor 1 is compatible with Recipient 2 and Donor 2 is compatible with Recipient 1. If you, your donor and the other pair are willing to participate in this “exchange,” a comprehensive evaluation process begins. The medical team will complete final medical tests and schedule the transplant on a date that works with everyone. Both transplants usually occur at the same day. This example used 2 pairs, but in fact any number of pairs is possible.
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Domino Paired Kidney Exchange
A domino paired kidney exchange starts with a non-directed or altruistic donor. Instead of just one person benefiting from their donation, this donor can allow many incompatible pairs to be transplanted. The difference in the example shown below from the “Paired Kidney Exchange” is that Donor #2 is not compatible with either recipient #1 or #2. As such, the altruistic donor allows the other pairs to be exchanged, and have the domino effect.
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Ongoing Domino Paired Kidney Exchanges
Most recently, altruistic or non-directed donors have begun initiating donor chains which have the potential to facilitate thousands of additional living donor transplants.
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Kidney Donor Waiting List Exchange
If a paired exchange cannot be found, living donors in certain areas of the country may be eligible for living kidney donor list exchange. In this type of exchange, a kidney donor who is not compatible with their intended recipient offers to donate to a stranger on the waiting list. In return, the intended recipient advances on the waiting list for a deceased donor kidney. This type of living donation is also referred to as list-paired exchange and living donor/deceased exchange. Since the growth of the different paired kidney exchange, waiting list exchanges have become less popular.