"The technical term is lupus nephritis," the "America's Got Talent" host says in a new interview on "Good Morning America." "It's a rare form of lupus that's just attacking my kidneys. They thought it was just kidney disease and then they were trying to figure out why my immune system was attacking my kidneys and that was sort of the root of it all."
After a relapse led to another hospitalization and the discovery that he had blood clots in his lungs, which caused him to take another look at his priorities. "My kidneys were in tip-top shape but I started to feel pain again," Cannon says. "And because of my schedule and everything I had a few blood clots in my lungs which then affected my heart as well. A lot of people have passed away from that and the doctor said luckily I was in such great shape and taking care of myself because a lot of people have been taken down by it."
Cannon, who is also chairman of the TeenNick network, decided to step down as host of his morning radio show to comply with his doctors' orders to take it easy.
Wife Mariah Carey has been helping with Cannon's recovery. "She made me an egg white sandwich before I left the house this morning. Those are the things I have to be eating now, no more bacon. She takes care of me, makes sure I'm eating what I'm supposed to be."