How is ankylosing spondylitis diagnosed?
There is no specific test to diagnose AS. The diagnosis of ankylosing spondylitis is based on evaluating the patient’s symptoms, a physical examination, X-ray findings, and blood tests. Symptoms include pain and morning stiffness of the spine and sacral areas with or without accompanying inflammation in other joints, tendons, and organs.
These blood tests are called ESR (erythrocyte sedimentation rate) and CRP (C-Reactive Protein). Test for the HLA-B27 gene can be helpful. Finally, X-rays may be taken to determine if there are changes in the joints at the bottom of the spine (sacroiliac joints).