He wanted to donate a kidney to help Jacksonville man. Instead, it saved his own life.

Pat O'Shaughnessy calls it his mission — his determination to donate one of his 64-year-old kidneys to a 31-year-old man with so much to look forward to.

He failed in that mission, he believes, and his voice breaks as he admits that.

But in that failure, he probably saved his own life. So he'll be around to continue the mission, he says, and he vows to stick with it until it succeeds.

O'Shaughnessy, retired from his title insurance business in Danville, Ill., traveled to Mayo Clinic in Jacksonville in October. He was there for a week's worth of intensive medical checkups to ensure that it was safe for him to give his left kidney to Perry Hess of Jacksonville, a family friend.

On the last day, a Friday, he was on a treadmill doing a stress test when he was called to meet with his transplant nurse, Turin Haas.

A scan showed a cancerous tumor in the kidney he wanted to donate.

It's your lucky day, doctors later told him: With kidney cancer, there are no early warning signs, and by the time it's found it's likely to have spread to both kidneys and the body's renal system.

“It’s ironic," O'Shaughnessy said. "I went there to help save a young man’s life, and he ended up saving mine.”

Spotting kidney cancer

After learning he had cancer, he and wife Elaine went back to Danville for a few days and then returned to Mayo, where he went through surgery on Halloween. His surgeon, David Thiel, was able to take out the whole tumor, saving his kidney, with no chemotherapy or radiation needed.

In an interview afterward, Thiel said he couldn't say for sure but that it's likely O'Shaughnessy's cancer, if not detected, would have spread. He also said it's not the first time that a serious medical issue had been spotted in a prospective donor during the extensive checkups each goes through beforehand.

Hess, who was lined up to receive O'Shaughnessy's kidney, saw him a couple of days after the surgery. Even after that experience, O'Shaughnessy was still on his mission.

“One of the first things Pat said, coming out of surgery was, 'Can I still give my kidney to Perry?' That speaks volumes about what an incredible person Pat is," Hess said.

For the record, medical professionals quickly told him no, he couldn't do that. A definite no. That will have to be up to someone else.

O'Shaughnessy is now at his winter home in Fort Pierce, recovering well. "I hope to be back to my misbehaving self," he said, "but Perry’s story goes on.”

Waiting for transplant

Hess grew up in the Jacksonville area, went to Ponte Vedra High School and then the University of Central Florida. He works at Fidelity Investments in Jacksonville.

He was born with just a single functioning kidney and had infections as a child that ended up scarring it. He started going to Mayo Clinic for treatment at 14 or 15.

His kidney functions declined over the years, and in 2022 he began lengthy dialysis treatments three times a week. He later began another kind of treatment that he does at night, at home, hooked up to a machine as he sleeps.

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He needs a transplant, but he had no blood type matches (he is an "O") among his family members. A brother, though, had pledged one of his kidneys to someone else if a donor comes forward, in what's called a "paired exchange."

Hess had met O'Shaughnessy only a few times, through his girlfriend, Kaitie Goodwin, who is from Danville and whose family has been longtime close friends with O'Shaughnessy's family.

Even so, O'Shaughnessy said that when he found out he had the same blood type as Hess, he knew what he had to do.

“My heart," he said, "convinced my brain this was something I wanted to look at,” he said.

O'Shaughnessy had been on a health kick after promising his granddaughter that he would be around for her wedding. He'd exercised, lost 40 pounds, was in the best shape of his life. Helping Hess seemed to be a part of this new way of living.

So he called Mayo Clinic and began the long application process to be considered a donor.

Mayo physician Shennen Mao, surgical director for living kidney donations and kidney transplants, said the waiting list for kidneys far exceeds the supply (Mayoclinic.org/livingdonor).

Prospective kidney donors, who can change their mind about their decision at any time, should have no side effects after the operation. Mao's known of donors who've later climbed Mount Kilimanjaro, chaired the evening news, run a marathon and had children.

"We expect them to live a full and complete and active life afterward," she said.

New chapters to write

Hess knows that O'Shaughnessy is deeply disappointed the transplant didn't work out, but he's delighted that something really good came out of it.

"I really think that this is an incredible story," he said. "His generosity and his selflessness is what ultimately saved his life."

Hess tried to make O'Shaughnessy feel better by assuring him that, for now, he is OK. "I'm doing fine," he said. "I feel better than I did. I’m in a routine. It’s not the greatest, but I'm getting by just fine."

O'Shaughnessy, though, said his mission will continue, as he urges people to think about becoming organ donors — and specifically thinking about helping Hess.

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"That's my journey now, finding someone else who will step up,” he said.

After his cancerous tumor was removed, O'Shaughnessy had a good cry, then sat down and wrote about his experiences. He noted his gratitude for having his life saved, as well as his disappointment that he wasn't able to help Hess.

He finished his story this way: "I will continue to cheerlead for Perry. He is a shy young man not looking for the publicity. I am NOT! I want to return to Jacksonville when Perry receives his kidney. To shake his hand and tell him OUR efforts did make a difference and that OUR story which became HIS story has now reached the final page, with two saved lives and two lives left to live. A new book can then begin with several chapters left to write."

This article originally appeared on Florida Times-Union: A man who tried to donate a kidney in Jacksonville saved his own life