TY - CHAP M1 - Book, Section TI - Ankylosing Spondylitis A1 - Kasper, Dennis L. A1 - Fauci, Anthony S. A1 - Hauser, Stephen L. A1 - Longo, Dan L. A1 - Jameson, J. Larry A1 - Loscalzo, Joseph PY - 2016 T2 - Harrison's Manual of Medicine, 19e AB - Ankylosing spondylitis (AS) belongs to the family of spondyloarthritides that also includes reactive arthritis (Chap. 162), psoriatic arthritis (Chap. 161), enteropathic arthritis (Chap. 165) juvenile-onset spondyloarthritis, and undifferentiated spondyloarthritis. Classification criteria based on their main clinical features of axial spondyloarthritis (Table 160-1) and peripheral spondyloarthritis (Table 160-2) have been developed that aide in early identification. AS is a chronic and progressive inflammatory disease of the axial skeleton with sacroiliitis (usually bilateral) as its hallmark. Peripheral joints and extra-articular structures may also be affected. Most frequently presents in second or third decade more commonly in men; strong association with histocompatibility antigen HLA-B27. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/04/18 UR - accessmedicine.mhmedical.com/content.aspx?aid=1128787415 ER -