Pls tell me how pain related to fibromylagia can de differentiated with ankylosing spondylitis pain ,I am feeling lower back pain and hip pain from last 3 month ,Hlab27 negative ESR CRP normal, MRI SI and PELVIC is normal , I have consulted 6 rhumatologist, but all of them denied possiblity of ankylosing spondylitis, can fibromylagia pain increases when stand up from sitting , when walk ,my pain is symmetrical and shifting location