Paired Kidney Exchange
When potential kidney donors cannot donate to their intended recipients because of mismatched blood type or tissue incompatibility, they can now enter the donor exchange program and donate to another person, which will allow their intended recipient to receive a kidney from another donor. See diagram below.
Once a donor and recipient are approved for the transplant, they join a private registry (computer program) of other people, consisting of pairs of donors and recipients who are not compatible with each other. A computer program then matches these donors and recipients to people with whom they are compatible.
Donor exchange can also be started by a non-directed donor, someone who donates anonymously without having a specific recipient. This situation starts a donor chain. See diagram below.
What Registry does University of Washington Medical Center use?
Today there are several major groups organizing kidney exchanges across the United States. These kidney registries are different than the national kidney waiting list through UNOS. The national kidney waiting list is for people to receive a kidney from a donor who is deceased. Patients on the kidney exchange registries may stay active on the national kidney waiting list through their transplant center while they are also registered with a kidney exchange program.
The University of Washington Medical Center belongs to the National Kidney Registry (NKR). The website for the national kidney registry is
Is there additional testing needed for Donor Exchange?
Living kidney donors and transplant recipients participating in the donor exchange have the same medical work up and evaluation as traditional living donation. However, there could be some additional testing required for the NKR.
Will I have to travel for the transplant or donation?
The donor kidney may be given to someone who lives in Washington or to someone who lives in another state. If a donor matches with a recipient in another location, the kidney would be shipped from the donor’s center to the recipient’s center. Shipping the kidney should not cause any decrease in success of the transplant.
Does a donor have to give a kidney before their recipient receives a kidney?
No. Typically, the kidney donation and transplant happen within the same 24 hours. There are alternate options, which can be discussed with your providers.
How long does it take to find a match once the donor and recipient are added ot the NKR?
The average wait time is about 10 months. How quickly a match can be found for a potential recipient can depend on blood type and whether there is a high level of antibodies against human tissue already present (high panel reactive antibody [PRA]). In addition the blood type of the possible donor can make a difference—if the donor has a more common blood type, a match can be found more quickly. The transplant center can evaluate more than one donor per recipient to be entered into the registry since this can potentially increase the speed of finding a match and allow more transplants to be done.
If you would like to participate in Paired Kidney Exchange or have questions, please contact University of Washington Medical Center at
Other information about living donation can be found at,