====== Ankylosing spondylitis diagnosis ======

Diagnosis by an experienced rheumatologist is the closest thing to a gold standard.
((van den Berg R, de Hooge M, Rudwaleit M, et al.
ASAS modification of the Berlin algorithm for diagnosing axial spondyloarthritis: results from the Spondyloarthritis Caught Early (SPACE)-cohort and from the Assessment of SpondyloArthritis international Society (ASAS)-cohort. Ann Rheum Dis. 2013; 72:1646–1653)).

The Assessment of SpondyloArthritis International Society (ASAS) presented its recommendations for a modified Berlin Algorithm
((van den Berg R, de Hooge M, Rudwaleit M, et al.
ASAS modification of the Berlin algorithm for diagnosing axial spondyloarthritis: results from the Spondyloarthritis Caught Early (SPACE)-cohort and from the Assessment of SpondyloArthritis international Society (ASAS)-cohort. Ann Rheum Dis. 2013; 72:1646–1653))
as a potentially useful tool for rheumatologists in diagnosing AS. SI joint involvement is the sine qua non for a definite diagnosis. Diagnosis is very involved, and includes: [[chronic low back pain]], buttock pain, sacroiliitis, family history, [[psoriasis]], inflammatory bowel disease or arthritis followed in ≤ 1 month with urethritis, cervicitis or acute diarrhea, an enthesopathy, and family history, and positive X-rays.

The (obsolete) New York Criteria was an early attempt to establish diagnostic benchmarks, but should no longer be used for definitive diagnosis.