(IOWA CITY, Iowa) -- Thirteen University of Iowa football players remain hospitalized after becoming ill with what the university says is a little-known muscle syndrome called rhabdomyolysis.
Rhabdomyolysis occurs when muscle is destroyed and the pigment in it that makes it red, called myoglobin, gets into the kidneys and can damage them.
At a press conference Wednesday, a spokesman said it's unclear how the students developed the condition.
"The causes of rhabdomyolysis are extensive. There may be a hundred different causes for this problem," said Dr. John Stokes, director of Division of Nephrology at the University of Iowa. He is not involved in the care of the players. "When it occurs in young, otherwise healthy individuals, one of the common scenarios we look for is a recent exercise."
Stokes said that it's unusual for so many people with different body types and genetic predispositions to come down with rhabdomyolysis at once. Although it attacks the kidneys, the condition almost always goes away.
"It does appear to be a little unusual, but apparently the common denominator for each of these individuals had to do with the fact that they were undergoing a workout, a heavy exercise program, and heavy exercise is known to produce this syndrome," he said.
Paul Federici, the director of football operations at the University of Iowa, said at the press conference he didn't know the exact structure of players' workouts, but said there were breaks and also plenty of water available.
When asked whether players may have been taking dietary supplements, some of which can cause rhabdomyolysis, Federici said he didn't know if they were taking any, and if they were, they are only allowed to consume substances that meet NCAA compliance. Rhabdomyolysis can be also caused by certain medications, such as statins to lower cholesterol.
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