Family of NASCAR driver Kyle Busch reveal cause of death

(NBC, KYMA) - NASCAR legend Kyle Busch died of pneumonia. That was the finding of a medical evaluation provided to the family Saturday.

The pneumonia was severe enough to progress into sepsis, which LED to a rapid and overwhelming decline.

The 41-year old driver died Thursday after he was found coughing up blood and lying on a bathroom floor at a training facility in North Carolina on Wednesday evening.

Busch had been struggling with a cold and sinus infection earlier this month, radioing his crew near the end of a NASCAR cup series race in New York that he needed a doctor to give him a shot at the finish.

That was May 10, where elevation changes and intense G-forces from the road course made him feel worse.

He won the NASCAR craftsman truck series race five days later.

His legacy includes two NASCAR cup series championships as well as 234 race wins, the most in racing history.

Busch was 41-years-old, and is survived by his parents, wife Samantha, and two young children.