When Neil Jeffs received a text message from his brother, he said he was “shocked” because his brother had just told him he would donate his kidney to him.

Neil, from Coventry, had already undergone a kidney transplant due to a health problem in 2005.

At that time, his mother was a match and for 17 years the transplant was successful, but then it began to fail.

However, although his younger brother, Paul, was willing to donate, there was a catch: he was no match for Neil.

It was then that they were helped by the UK Live Kidney Exchange Programled by NHS Blood and Transplant.

They use algorithms to match the hundreds of registered recipients at any time to find the best recipient-patient combinations.

In Neil’s case, he benefited as Paul’s kidney was donated to another person on the transplant list, allowing Neil to have a stranger’s kidney.

The overall process involved three recipients and three donors and Neil said the best way he could think of to explain it was as a chain for a series of home sales.

“All the links are very closely related and if one of the links fails, that particular chain fails at that time,” he said.

His brother Paul said he was told each kidney had six unique numbers and “when my mother donated it, I imagine it must have been quite a match for Neil.”

“But when we did the test, we found out that… our blood was fine, I think there were no antibodies at that time, so there was no problem with that.

“However, of those six numbers, there wasn’t a single one that matched, so what they do is, as I understand it, across the country they just throw it into a database.

“Then it will generate a match with someone who is somewhere in the country and then… sure enough we did it, it turned out to be a six-person exchange.”

The younger brother said he thought he had seen a change in his brother at the end of 2022 and “we all visibly noticed that Neil seemed to lack energy.”

“They told Neil that his kidney… wasn’t working, so I spoke to my wife,” he added.

“I think it was around February 23 when I messaged Neil and said… ‘I’m willing to donate.'”

Neil said: “When I got the text saying he was willing and able to donate his kidney, I was blown away.

“I’m very excited to think…what Paul has done.”

The kidney exchange program is anonymous and confidential: people do not know who their donor or recipient is.

And trades only take place if each pair (up to three in total) can be matched. No patient misses it.