19 High School Footballers Struck by Mystery Illness Elevated enzyme levels could have led to kidney failure By Evann Gastaldo, Newser Staff Posted Aug 23, 2010 12:56 PM CDT 8 comments Comments Elevated enzyme levels could have led to kidney failure. (AP Photo/Paul Sancya, File) (Newser) – Nineteen high school football players from Oregon were struck with a mystery illness after attending football camp, with three undergoing surgery to relieve pressure on their muscles. The players, who worked out in a wrestling room that got as hot as 115 degrees, all had elevated levels of creatine kinase (CK), an enzyme released by injured muscles. One player describes his triceps and forearm muscles swelling “to the verge of popping.” Vigorous exercise can cause high CK levels; so can certain food supplements—but some players insist no supplements were taken. Officials say the cause of the players’ illnesses is still unknown, but a doctor tells the AP the high temperature and dehydration are likely factors. The McMinnville High School athletes are not being tested for steroids, but blood tests will show whether they ingested creatine via a protein supplement.