How is human leukocyte antigen (HLA) B27–associated ankylosing spondylitis diagnosed?

Updated: Apr 09, 2021
  • Author: Huy D Nguyen, MD, MBA; Chief Editor: Andrew A Dahl, MD, FACS  more...
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Radiographs of sacroiliac joints show sclerosis and narrowing of the joint space. This is followed by ligamentous ossification, and osteoporosis. Both sacroiliac joints usually are involved but can be asymmetric initially.

Ankylosing spondylitis may first present to an ophthalmologist in the form of AAU. A family history or symptoms of back problems and a positive HLA-B27 are highly suggestive of the diagnosis. Sacroiliac films should be obtained, and the patient should be referred to an internist or a rheumatologist to monitor and manage the risk of deformity and systemic complications such as pulmonary apical fibrosis, aortitis, and aortic insufficiency.

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