Ankylosing spondylitis

1. What are the major seronegative spondyloarthropathies?
2. What is the hallmark of ankylosing spondylitis?
3. What genetic marker is associated with AS?
4. What skeletal symptoms are associated with AS? What is the frequency of different sites of involvement?
5. What are the extraskeletal manifestations of AS?
*6. What are the HLA B27 pos diseases?

Answers:
1. Ankylosing spondylitis, Reiter's syndrome, psoriatic arthritis, and arthritis of inflammatory bowel disease. Most are RF- and HLA B27+.
2. Bilateral sacroiliitis.
3. HLA-B27 pos in 90%.
4. Sites of involvement: (1) SI jt, (2) Lumbar vertebrae, (3) Thoracic vertebrae, (4) Cervical vertebrae. Initially may be assymetric, lumbar morning stiffness, decreased lumbar lordosis and incr thoracic kyphosis, enthesitis, respiratory restriction.
5. Fatigue, weight loss, low grade fever, acute iritis (pain, photophobia, blurred vision), aortitis, apical pulmonary fibrosis, amyloidosis, cauda equina syndrome, C1-C2 subluxation.
*6. AS, Reiter's syndrome, psoriatic arthritis, enteropathic arthropathy, pauciarticular JRA.