Someone who has kidney failure–often called End Stage Renal Disease (ESRD)–has three options for treatment: dialysis, a transplant from a deceased person, or a transplant from a living person.
Why is living kidney donation a consideration? First, dialysis is only a temporary solution. While someone can remain on dialysis for many years, it is not a cure and it is time consuming with treatments as frequent as three times a week for four hours each time. Transplantation from a deceased donor is a preferred alternative, but the number of donated organs does not keep up with demand. United Network of Organ Sharing (UNOS), the organization responsible for allocating donated organs for transplant, reports there are nearly 100,000 people actively waiting for a kidney transplant, and that number increases daily. Yet, there are fewer than 15,000 kidney transplants from deceased donors each year. Consequently, living donation is seen as a way to address the gap.
There are several reasons why living kidney donation is an important consideration:
- Transplantation has been shown to be less costly than dialysis over the long run.
- The waiting time for a transplant recipient can be significantly reduced.
- The procedure can be scheduled at a time convenient for both the donor and recipient.
- The quality of the donated organ tends to be better than organs from deceased donors.
All of these factors have yielded positive results for recipients. There is less rejection and lower doses of anti-rejection drugs. The transplanted kidney, or “graft,” has better odds of surviving if from a living donor, as show in the following UNOS data for kidney transplants in the U.S:
Kidney Graft Survival Rates
Time after donation
From deceased donors
From living donors
Types of Living Donation
There are different types of living donation, which generally are determined by two factors–(1) whether the donor and recipient are biologically related and (2) whether the donor is directing the donation. “Directing” means the donor identifies the specific person to whom he or she is donating. The different forms of donation and the terminology used to describe them are as follows:
- Living related donation: the living donor directs the donation to a specific recipient who is a blood relative such as a parent, child, or sibling. Looking at UNOS data for living kidney donations, about 75% are living related donations.
- Living unrelated donation: the living donor directs the donation to a specific recipient who is not a blood relative such as a spouse, a friend, or co-worker. About 24% of living kidney donations are living unrelated donations.
- Living non-directed donation: the living donor does not direct the donation. Instead, the recipient is selected from a list of compatible people on a kidney waiting list. This form of donation is also sometimes called “anonymous” donation because the donor and recipient do not necessarily ever meet. Only about 1% of living kidney donations are of this type.
Another type of living donation is called paired exchange. In this situation, there are at least two donor/recipient pairs where the donors are not able to donate to the directed recipients because of blood types that aren’t compatible or because of a positive crossmatch. However, the donor in one pair is compatible with the recipient of the other pair, and vice versa, allowing the donor of one pair to donate to the recipient of the other pair. In a growing number of situations, more than two donor/recipient pairs are linked in an extended “chain” of donation. These chains have included as many as 34 donor/recipient pairs.
Here’s an example of a paired exchange. Assume in the first donor/recipient pair, the donor, Jim, is blood type A and the person he’d like to donate to, Lisa, is blood type B. Jim can’t donate to Lisa because they have incompatible blood types. In the second pair, the donor, Niki, is blood type B and she’d like to donate to Mike, but he’s blood type A. They are incompatible. Paired exchange provides the solution: Jim donates to Mike (both blood type A), and Niki donates to Lisa (both blood type B). Organizations have been formed to facilitate the matching of donor/recipient pairs. As a result, the number of paired exchanges has increased significantly.
Currently there are about 6,000 living kidney donors each year. They come from all walks of life and locations. Here is a summary of the demographic characteristics of U.S. living kidney donors:
- Most (45%) were between the ages of 35 and 49.
- 71% were white, 13% black, 12% Hispanic, and 2% Asian.
- The majority (58%) of donors were female.
- 45% had type O blood, 38% type A, 13% type B, and 4% type AB.
A Brief History of Living Kidney Donation
Living kidney donation began in 1954 with the donation by Ronald Herrick to his identical twin, Richard. The procedure was performed by Dr. Joseph E. Murray at Peter Bent Brigham Hospital in Boston, MA. Being identical twins was an advantage because there was no risk of rejection–the tissue types were identical. The procedure was a success, and Richard lived a healthy life until his death eight years later of causes unrelated to the donation. Ronald Herrick passed away in 2010 at age 79 following complications from heart surgery.
Living kidney donation is now commonplace. In fact, kidney transplantation is no longer considered experimental and is routinely covered by medical insurance programs.
In 1995, a surgical procedure using laparoscopic techniques to procure the kidney from the donor was pioneered. This less invasive procedure, called “laparoscopic nephrectomy,” has replaced “open nephrectomy” as the most common surgical procedure because of more positive outcomes for the donor.
An ethical issue is the growth in the number of donations where there is no biological or emotional tie between the donor and recipient. The number of these donations has been increasing since 2000, facilitated by the development of more powerful anti-rejection drugs, which has reduced the importance of tissue matching and, therefore, the need for close biological ties. It has also been aided by the use of web sites that connect potential donors with potential recipients even though the individuals are essentially strangers. On one side of the issue, such donors increase the number of transplants at a time when they are desperately needed. Some argue these donors also receive personal benefit and increased self-esteem from donating. On the other side of the issue, some ethicists and medical professionals are suspicious of people who meet over the Internet, assuming the probability of illegal compensation or coercion is higher. Ethicists are also concerned that solicitation of an unrelated person to donate bypasses the safeguards built into the current organ allocation system. In response to these concerns, some transplant centers do not allow unrelated living donor transplants unless there is a biological or emotional relationship between the donor and recipient. People who are willing to donate anonymously or who met recipients on the Internet have been prevented from donating at these transplant centers.
An experimental development in living donation is the use of the donor’s bone marrow to minimize or even eliminate the need for anti-rejection drugs by the recipient. The technique, called chimerism, has the donor first donating bone marrow, which is used to change the recipient’s immune system. The donor then donates a kidney. Anti-rejection drugs are used initially, but eventually the recipient does not need to take those drugs. This process was tried on five patients. The transplant teams provided an update in January 2008, five years after the procedure, reporting that one patient rejected the kidney, and the other four patients have kept the donated kidney without the use of anti-rejection drugs. Oddly, the authors of the report did not share any information whatsoever on the fate of the five donors who provided the bone marrow and kidneys essential to the procedure. This process is still considered experimental and is not available.
In 2017, a new program was proposed called a “voucher” that involves a donor donating a kidney before an intended recipient may need a transplant. The donor’s current donation creates a voucher for a future kidney transplant for the intended recipient. The purpose is to allow for a donation when it is more convenient or practical for the donor. For example, a child with a genetic disposition for kidney disease may have his or her grandparent donate now, even though the child does not currently have kidney disease because the grandparent would likely be too old to donate when the child actually has the need. The grandparent’s current donation creates a voucher that can be redeemed by the child in the future if he or she needs a transplant. A voucher program has been implemented by the National Kidney Registry and is described here.
About Living Kidney Donation
- Why living kidney donation?
- The tap on the shoulder (being asked to donate)
- Now…about your health (donor evaluation)
- The gift (the surgical process)
Information source: http://livingdonorsonline.org