"I was pretty scared, but I kind of just said at that moment, I've got to take the bull by the horns. I've got to make the best of this and take the cards that were dealt to me. And that's what I've been doing for two-and-a-half years, almost," he said.
But life with Wegener's has not been without its travails.
"I went from being a healthy 6-foot-4 teenager that could run 100-meter wind sprints all day long to having trouble climbing a flight of stairs," said Cosner.
That has been a great challenge, he said, at college, where "everything here is hills and stairs."
But he has made some adjustments. While he excelled at lacrosse in high school, he has picked up activities he enjoys that don't require the same stamina.
He has taken up bowling and tournament bass fishing, and stays in shape by lifting weights, in between time with friends and his school work.
Games like basketball are out, however. "I get really winded pretty quick. Once I get up the court I have to stop. It's like a severe asthmatic, almost," said Cosner.
One of the reasons for the difficulty in diagnosing Wegener's is how it appears in patients.
"There can be a whole spectrum as to how this can first present," said Dr. Carol Langford, a staff physician in rheumatic and immunologic disease at the Cleveland Clinic.
She explained that some people may have symptoms for weeks or months while others will become ill in a matter of days.
"It can be a challenging diagnosis to make," she said.
Langford has been one of Cosner's doctors in Cleveland. Cosner travels there every three to five months for surgeries to treat complications in his lungs that have resulted from the disease.
Because of the nature of Wegener's, some of its treatments are similar to those used for cancer patients.
"We think the immune system is overactive, and our treatment is geared toward trying to address this," said Langford.
Treatment typically includes smaller doses of chemotherapy drugs (given orally, rather than injected) designed to reduce the immune response.
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