Jerri Kurdila and Eric Amshoff had both worked at Duke Energy in Monroe, Ohio, for years. She as a gas coordinator and he as a field technician for the power company.

“I knew he worked down the hall, enough to say hi,” Ms. Kurdila says.

That was until she saw an unusual plea on his behalf. Mr. Amshoff’s sister-in-law posted fliers around the office in July 2015, explaining that he suffered from hereditary polycystic kidney disease and needed a transplant. With his blood type, O-positive, he faced a seven-year wait on the national organ donor registry. Would anyone consider getting tested as a possible living kidney donor?

Seeing the photo of Mr. Amshoff and his wife Jodie on the fliers triggered something, says Ms. Kurdila, 53, who is married with two grown sons. “I had the same blood type, and a little voice inside me said, ‘Just go get tested. What would it hurt to see if you’re a match?’ ”

So she did. And she was.

The transplant took place in March of 2016 at the Christ Hospital in Cincinnati.

“What Jerri did for me,” says the 49-year-old Mr. Amshoff, getting emotional. “I’m still amazed every day.”

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