You Be the Doctor: What's Making Evan So Sick?

The Diagnosis

"After we did the biopsy, the results came back the same day," Akhter said. "The pathologists told me two things: One, that Evan had a fungal pneumonia. And two, they also found clusters of what are called granulomas."

Evan had numerous types of fungus in his lungs, as well as the granulomas, which are white blood cells surrounding a foreign invading body.

"Because they can't kill it, they surround it," said Keith.

Evan's white blood cells weren't working. A rare genetic disorder, chronic granulomatous disease of childhood, or CGD, could cause that. But if it was genetic, wouldn't his twin sister have it, too?

As it turns out, not with CGD, which is carried by the mother but only shows up in boys.

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When three members of the McClow family got a bad cold, 16-month-old Evan didn't get better.

"Dr. Akhter gave us the diagnosis of CGD. Yet, I have a son who's still lying in a hospital bed in critical care," Teresa said. "I felt as though he wasn't going to make it at this point."

"We're treating him, but it looked like he was still getting worse," Akhter said.

Doctors decided that because the white blood cells weren't working, they'd try giving him a white blood cell transfusion.

"After laying there for a month lifeless, suddenly, he started to try to open his eyes," Keith said. "Once he started responding to the treatments, Evan recovered pretty rapidly."

Evan will always need medicine for his white blood cells, but now he's playing with his twin sister again.

"Evan is jovial. And funny," Teresa said. "Looking at him, you would never know what Evan experienced. What he went through."

So if you chose option C: Genetic Disease, you were right. Evan has CGD, a genetic disorder of the immune system, which allowed a host of infections to invade his body.

For more information about CGD, visit http://cgd.cultivatecommunity.com and http://www.cgd.org.uk/.