Brooklyn, New York (CNN)It was a Friday afternoon like any other. I ate lunch, dropped off my dry cleaning, then stopped by my local Target to pick up some prescriptions.
But on the way to the counter I noticed a man in a black coat, wearing a backpack bearing a sign: "In need of a kidney for my wife, B+. 917-442-6202."
Unsure what to say, I quickly snapped a photo. And then he was gone. Although I generally hate posting pictures of people online without getting their approval, I decided to share the image on Twitter since his face wasn't in it -- and because the message was so important.
Within a few hours, my picture of this man -- whom I've since identified as Raymond Thompson -- had gone viral. Celebrities such as Zach Braff, Martina Navratilova and Evan Rachel Wood shared it. Actress Sarah Hyland, who recently revealed she had a second kidney transplant, shared the image, too.
Nearly a week later, the photo was past 23,000 retweets and 35,000 likes.
Thompson, who lives in Brooklyn with his wife Mylen and their 4-year old daughter, Rachel, doesn't even have a Twitter account. But he knew something was going on when his phone began lighting up with calls and texts from unfamiliar numbers all over the world. Strangers were offering to give Mylen a kidney.
When I called Raymond, he recognized my name because others had sent him screenshots of my tweet.
Mylen met her future husband in an AOL chat room in 2000 and they bonded over their love of pro wrestling. She was diagnosed with kidney disease two years ago.
"She called me at work and said, 'Babe, you need to come home right now.' She said, 'I can't feel my right side. It's numb,' " Raymond told me. Now "she goes to a [dialysis] center for three hours, three days a week. There's a machine that filters your blood. It takes a lot out of you."