Ankylosing spondylitis

Background

  • Ankylosing spondylitis (AS) is a chronic inflammatory disease of the axial skeleton with variable involvement of other joints or even nonarticular structures
  • 3x more common in males than females
  • Typically diagnosed in young adults between the ages of 20 and 30 yrs
  • Often associated with other autoimmune disorders
  • 90% of people with AS express the HLA-B27 genotype

Clinical Features

  • Spinal pain, particularly in the lower back, is usually the first and most common symptom of AS
    • Begins in early adulthood (before 45 yrs)
    • Has a gradual onset
    • Lasts longer than three months
    • Is worse after rest (for example, in the morning) but improves with activity
    • Can cause morning stiffness lasting more than 30 minutes
  • Fatigue
  • Can also be associated with anterior uvetitis, bowel ulcers and spinal fractures are 4 times more common in patients with AS [1]

Differential Diagnosis

Lower Back Pain

Diagnosis

  • There is no direct test for AS
  • ESR, CRP can be elevated but not sensitive or specific
  • Xray lumbar/sacroiliac: The earliest changes in the sacroiliac joints shows erosions and sclerosis
    • Progression of erosions leads to pseudo widening of the joint space and bony ankylosis AKA "Bamboo Spine"

Often X-ray findings lag about 10 years from initial progression of disease

"bamboo spine"
  • CBC
  • Chem 10
  • UA
  • Genetic testing for HLA B27 ( > 90% of people with AS have this gene, though by it's self is not specific)

Management

  • There is no cure for AS, although treatments and medications can reduce symptoms and pain
  • Exercise and posture training should be part of the treatment program for everyone with AS
  • NSAIDS
  • Sulfasalazine can be used in people with peripheral arthritis, but for axial involvement, evidence does not support it [2].
  • Lack of evidence for methotrexate [3] or steroids.
  • Tumor necrosis factor-alpha blockers, such as the biologics etanercept, infliximab, golimumab and adalimumab, provide good short-term effectiveness though long term management is currently being studied

Disposition

  • Often diagnosis will not be made in ED but if made in ED often can be discharged home with primary care follow up or rheumatology follow up

See Also

  • Arthritis

External Links

References

  1. Westerveld LA, Verlaan JJ, Oner FC. Spinal fractures in patients with ankylosing spinal disorders: a systematic review of the literature on treatment, neurological status and complications. European Spine Journal. 2009;18(2):145–156
  2. Chen J, Lin S, Liu C. Sulfasalazine for ankylosing spondylitis. Cochrane Database of Systematic Reviews 2014, Issue 11. Art. No.: CD004800. DOI: 10.1002/14651858.CD004800.pub3.
  3. Chen J, Veras MMS, Liu C, Lin J. Methotrexate for ankylosing spondylitis. Cochrane Database of Systematic Reviews 2013, Issue 2. Art. No.: CD004524. DOI: 10.1002/14651858.CD004524.pub4.