Ver el código de «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
*[[Uveitis]] is common extra-articular manifestation, seen in 30% of patients

==Clinical Features==
*[[back pain|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 [[uveitis]], [[arthritis]], [[psoriasis]], enthesitis, [[IBD]] and [[spine fractures]] (4 times more common in patients with AS <ref> 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 </ref>)

==Differential Diagnosis==
{{Lower back pain DDX}}

==Evaluation==
*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 [[File:5269907670e86d9b415221efa30bf166.jpg|200px|thumb|right|"bamboo spine"]]
*CBC
*Chem 10
*[[Urinalysis]]
*Genetic testing for HLA B27 ( > 90% of people with AS have this gene, though by itself is not specific)

==Management==
*There is no cure for AS, although treatments (e.g. exercise, posture training) and medications can reduce symptoms and pain
*[[NSAIDS]]
*[[Sulfasalazine]] can be used in people with peripheral arthritis, but for axial involvement, evidence does not support it <ref>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.</ref>. 
*Lack of evidence for methotrexate <ref>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.</ref> 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==
<references/>

[[Category:Rheumatology]]