Mark Reale, guitarist for Riot, is in critical condition at a San Antonio, Texas hospital due to complications from Crohn's disease. Reale formed Riot in 1975 and the band has enjoyed a successful career to this day, sharing the stage with everybody from AC/DC and Black Sabbath to Sammy Hagar and Kiss.

A post on the group's official site states that Reale was practicing for Riot's upcoming U.S. tour when he was "felled by a severe onset of Crohn's symptoms, leaving him in the Intensive Care Unit" at an unnamed hospital. The story goes on to caution fans that Reale may not be able to perform with the band on those upcoming shows, which of course is of secondary concern to his health.

According to WebMD, Crohn's disease is a lifelong inflammatory bowel disease in which parts of the digestive system get swollen and have deep sores called ulcers. It makes it hard for the body to absorb nutrients from food.

Reale has been battling this condition for most of his life according to the post, to the degree that his bandmate Mark Flyntz recorded a "major portion" of the guitars on the band's most recent album, 2011's 'Immortal Soul.'

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