Ankylosing spondylitis

• Facts:
  Chronic inflammatory disease of pelvis and spine
  Causes sacroilitis, leading to fusion of affected joints
• History / PE:
  Fatigue
  Intermittent hip pain
  LBP worse in mornings, improves with activity
  Enthesitis (pain where tendons/ligaments attach to bone)
  Anterior uveitis
  Heart block
• Diagnosis:
  Positive HLA-B27 in 85-95% of cases
  Negative RF, ANA
  Radiographs show fused sacroiliac joints ("bamboo sign")
  ESR or CRP increased in 75% of cases
• Treatment:
  NSAIDs
  TNF inhibitors or sulfasalazine
• Complications:
  Chronic AS can lead to increased risk of vertebral fractures
• See Also:
  Seronegative spondyloarthropathy
• Associated With:
  Restrictive lung disease (fusion of costovertebral joints)
• Differential Diagnosis:
  Reactive arthritis
  Psoriatic arthritis
  Enteropathic spondylitis