Among all the candidate autoimmune diseases, AS possesses the best evidence of bacterial infection as a crucial trigger. In 1%-4% of individuals with infection of the gastrointestinal tract with Enterobacteriae or the urogenital tract with Chlamydia trachomatis, a so-called reactive arthritis develops in the following 6 weeks. Between 30%-70% of these patients are positive for HLA-B27, and among these patients 20%-40% develop the full clinical picture of AS 10-20 years after the initial infection .
Similarly, 10%-20% of patients with inflammatory bowel disease (IBD) develop peripheral arthritis at some time during the course of their disease. AS has been reported in between 5%-10% of patients with IBD with those positive for HLA-B27 at especially high risk: in one study of 231 Crohn's patients, 54% of HLA-B27-positive patients developed AS compared to 2.6% of those who were negative . Thus, at least half of the HLA-B27-positive IBD patients will develop ankylosing spondylitis that cannot be differentiated from the primary form of the disease. Stimulation of the immune system in IBD by translocated gut bacteria therefore might well trigger AS, and T cells primed in the gut could recognize related bacteria or cross-reacting self-antigens in the joints . When the T cell repertoire from an inflamed joint was compared with gut biopsies from a patient who had both IBD and arthritis, the same antigen specificities were found in both compartments. Furthermore, the CD8+ T cell receptor repertoire matched that of lymphocytes from patients with ReA , supporting the concept that there may be common dominant bacterial antigens in AS and related diseases. Finally, although fewer than 10% of AS patients complain of preceding infections or IBD, infections with ReA-associated bacteria and gut lesions in IBD patients are often subclinical .
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Thank you for deciding to learn more about the disorder, Osteoarthritis. Inside these pages, you will learn what it is, who is most at risk for developing it, what causes it, and some treatment plans to help those that do have it feel better. While there is no definitive “cure” for Osteoarthritis, there are ways in which individuals can improve their quality of life and change the discomfort level to one that can be tolerated on a daily basis.