Kidney offering and matching

When an organ donor is notified to NHS Blood and Transplant (NHSBT) the following details are recorded: their renal function, blood group, and tissue type. The donor information is then added to the national database which identifies the most suitable recipient for the kidney.

Suitability is determined by a complex mathematical process which gives priority based on the following factors, each of which are given points:

• The compatibility of the blood group
• Length of time on the waiting list – one point for every day waiting
• The similarity of the donor and recipient’s tissue types – the better the match the more the points
• Whether the recipient’s tissue type is unusual such that it would be particularly hard to find a transplant for that person. Difficult to match patients are awarded more points in order not to miss the rare chance of a transplant
• Whether the recipient has developed antibodies that reduce the likelihood of a match. This is called sensitisation - highly sensitised patients get more points.
• The age of the recipient – children get more priority

When a potential recipient is identified NHSBT contact the transplant centre and offer the kidney for the potential recipient. Not all offers are accepted. There may be problems with the donor that mean the kidney has a higher risk of failure than average, a risk the transplant centre is not willing to accept. Alternatively there may be problems with the recipient, such as a recent infection, that makes them unsuitable to undergo transplantation at that time.