The histocompatibility antigen HLA-B27 belongs to the molecules of the Major Histocompatibility Complex Class I (MHC-Ι) and is strongly linked to the occurrence of various forms of spondyloarthritis, mainly ankylosing spondylitis (AS), reactive arthritis (Reiter’s disease), juvenile rheumatoid arthritis, and, sometimes, posterior uveitis. It is used as evidence in a total of indications, symptoms, and laboratory tests to support or exclude the diagnosis of the aforementioned autoimmune diseases.

 TEST

• Molecular detection of the HLA-B27 allelomorph