Ankylosing spondylitis (AS) is a disease characterized by inflammation of the sacroiliac joint and spinal attachment points. Strongly associated with HLA-B27. Certain microorganisms, such as Klebsiella, share common antigens with their own tissues in susceptible individuals and can elicit an abnormal immune response. It is a chronic inflammatory disease characterized by limbs and joints, and fibrosis and ossification of connective tissue around the annulus fibrosus and joint. Ankylosing spondylitis is a rheumatology category,it is a seronegative spondyloarthropathies. The reason of the disease is not yet clear, it is a chronic disease of the main spinal lesions, involving the sacroiliac joint, causing spine rigidity and fibrosis, resulting in varying degrees of eye, lung, muscle and skeletal diseases,that is an autoimmune disease.
