An 83-year-old man has achieved a double by becoming the oldest living kidney donor in the UK and the oldest person in the country to give a kidney to a stranger.
Nicholas Crace is the latest member of an exclusive club known as altruistic donors - someone who gives a kidney to somebody on the NHS waiting list whom they do not know.
The former charity director, from Overton, Hampshire, said: "I knew that 7,000 people are waiting for a kidney and that one person dies almost every day while waiting.
"I couldn't have lived with myself with the knowledge that I had had the chance of changing someone's life and turned it down."
The operation, which took three hours, was carried out recently at the Queen Alexandra Hospital, Portsmouth.
Tests at the hospital revealed that the widower's kidneys functioned as well as those of someone in their 40s.
Mr Crace said: "The surgeon congratulated me on the perfection of my kidneys.
"In fact, given a halter, he would gladly have led me into the winner's enclosure at the Smithfield Show to have a rosette pinned on."
Annabel Ferriman, chairwoman of Give a Kidney - One's Enough, a charity dedicated to raising awareness of altruistic donation, said: "Altruistic donors are very special people.
"They have the imagination to understand the suffering that people go through on dialysis while waiting for a transplant and the courage and generosity to do something about it."
Mr Crace explained that his thoughts turned to donating a kidney after his wife Brigid died last summer.
He also realised he was too old to be a bone marrow or blood donor, having given blood 57 times previously.
Mr Crace, who is a volunteer driver for a local hospice, said: "I cannot remember quite what put the idea of being a living kidney donor into my mind but in September 2011 I thought that it might be worth investigating.
"After all, I was in good health, had no dependants and had plenty of time at my disposal.
"Giving a small part of me to someone else will make little difference to my life but a huge difference to someone else's - it was an easy decision for me to make.
"I was lucky to be in a position to help someone else less fortunate than myself."
The process involved Mr Crace undergoing a number of tests during 14 hospital visits in a six-month period.
Consultant surgeon Sam Dutta, who performed the operation, said: "We know from numerous studies that a living donor kidney performs better, works quicker and lasts longer than one from a deceased donor.
"All the detrimental factors related to being on dialysis are completely taken care of by a good, functioning kidney.
"An altruistic donor coming forward is an amazing thing for us. The recipient just gets a new lease of life."
Almost 100 people have donated a kidney since the altruistic living donor scheme was launched in the UK in 2006 and in 2011 a further 1,000 people gave a kidney to a relative or friend.