The main thing we look at when determining if a donor can donate directly to their intended recipient is blood type. There are four blood types—O, A, B and AB. Donor with blood type O are considered the “universal donors” as they can donate to a recipient with any blood type. Recipients with blood type AB are considered the “universal recipients,” as they can receive an organ from a donor with any blood type.
If a recipient has had a previous transplant and/or blood transfusion, they might have developed antibodies—proteins in the blood produced in response to an infection—against the transplanted organ or blood product. All recipients are tested to see if they have antibodies that could react negatively to the donated organ. If they do, the donor candidate is also tested. During the donor evaluation, we will discuss antibodies in more detail.
When determining donor/recipient compatibility, we also consider other elements such as age or size differences. If the donor and recipient are not compatible for any reason, the living donor can still donate their kidney on behalf of their loved one in need through the National Kidney Registry’s (NKR) paired exchange program. In the paired exchange, the donor would donate to a compatible recipient and their loved one would receive a transplant from a compatible living donor as part of a swap. Additional information is provided about the paired exchange during the evaluation process.