High ASO titer but no diagnosis

Patient: Dear Doctor,My daughter has had a high ASO titer for a few months now. 1200 is the level on her reports.We still do not know what is wrong with her. This started in June with serevre joint pains,swelling,numbness on and off. Fatigue,headaches,back pains as well. She is 23yrs old. She has been seeing a Rhumeotologist,Nurologist, and our internist. She has been on Clindimyacin 300mg for a couple months her numbers have not gone down. I have no idea what she has but out ENT said maybe Rheumatic Fever. What do you think we should do and your opinion on this matter would be greatly appreicated.