Anykylosing spondylitis is a type of autoimmune disease
1) type of spondyloarthropathy (disease of the joints) marked by inflammatory arthropathy of the sacroiliac joints and vertebral column 2) first occurs in sacroiliac joints and then ascends into the spinal column, with posterior joints becoming fused 3) result is loss of weight bearing onto vertebral bodies with development of osteoporosis 4) bone bridges form between vertebrae.
Signs and Symptoms
1) severe spinal immobility 2) presents with low back pain 3) one third of patients develop involvement of peripheral joints, such as shoulders, hips, and knees
Characteristic Test Findings
Radiology – 1) “bamboo” spine Laboratory–2) rheumatoid factor is negative
1) intervertebral disc becomes partially replaced by bone marrow 2) focal inflammatory patches in all layers of heart wall and aorta 3) chronic synovitis with destruction of articular cartilage
1) 10% of patients develop dilated aortic ring with scarred cusps (functional result is aortic regurgitation) 2) 5% develop amyloidosis 3) increased incidence of bronchocentric granulomatosis 4) increased incidence of uremia 5) lung fibrosis 6) cauda equina syndrome
1) most likely to occur in young men 2) peak onset in early 20s 3) 90% have HLA-B27 (but only 1% of patients who have HLA-B27 develop ankylosing spondylitis
1) daily stretching and flexibility exercises 2) NSAIDs 3) sulfasalazine 4) methotrexate 5) alpha-TNF antagonists like infliximab and etanercept 6) case reports exist of antibiotics being effective, especially against Klebsiella
Tips for USMLE
1) 90% of patients have HLA-B27 2) if patient is a 22 year-old apparently health third baseman who has new onset back pain and difficulty fielding grounders and who also has a new cardiac murmur on examination, think ankylosing spondylitis
Ankylosing Spondylitis says
There is current research going on to determine the causes of the inflammation that is part of ankylosing spondylitis. Some researchers believe this inflammation begins with a bacterial infection that causes the immune system to react. Once the bacterial infection is gone, a normal person’s immune system reverts to ‘protect and scan’ mode, but in a person affected by AS their immune system stays in the ‘attack’ mode. This causes tissues to become inflamed. Other researchers think that AS begins when the intestinal defenses break down, causing bacteria to get into the bloodstream, and then to the joints most affected by this arthritis, the sacroiliac joints.