Seronegative spondarthritis is a group of inflammatory joint diseases, distinct from rheumatoid arthritis, that are thought to share similar pathogenesis.
There is a marked degree of extra synovial inflammation, especially of the enthesis but also affecting capsule, periarticular periosteum, and cartilage and subchondral bone.
An association with HLA-B27 occurs in all serongeative spondarthritides but is particularly strong for ankylosing spondylitis and Reiter’s disease and when there is sacroiliitis, uveitis or balanitis.
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