My son is 13 years old. He became sick in June with a sore throat and fever. He then starting having symptons of chest pains, muscle aches/cramps, joint pain that moved from jt. to jt., with no redness or swelling that we noticed. He had shortness of breath and wheezing, that was treated as exercise induced ashtma ( He runs cross country). We never noticed a rash. He had extreme fatigue and would fall asleep at school. We went to the ER one night and they put him on an antibiotic for bronchiolitis. Throughout all this we regularly visited our family physician and he ran several blood tests and had echo's done. His echo came back that he had some I believe mitral valve leakage, but everything else was okay. His ASO titre came back at 640 and his ANA was positive. Our family physician treated him for rheumatic fever with a penicillin injection, until we saw the cardio. Based on the fact that he did not have joint swelling, a rash and no carditis he was not diagnosed with rheumatic fever. We also saw a rheumotologist. My question is could the Antibiotics from the ER have masked any symptons of rheumatic fever? We are not treating him for anything. His ASO titres continue to remain high arond 550. I am concerned he will turn up with heart trouble down the road. I am concerned that he may have had mild rheumatic fever. Thank you for any advice you can give us. He continues to have some fatigue, mucsle cramping at times and occasional jt. pain. He will occasionally complain that his chest and around his back hurts.