Hi and welcome to Kickas, this is a great place to learn of alternatives... this place saved me 4 yrs ago now. You can read the success stories thread to see my story.
I have yet to find a rheumatologist that believes in diet as an effective approach to treating AS. I did have one Primary Care Physician that was supportive. Guess you just have to keep asking and networking if you want to find someone. I do know one rheumy that was in Scottsdale (can not recall name) that was more open, heard him speak at a conference.
Tim