Bechterew's Disease (Ankylosing Spondylitis, AS) [M45.09]
OMIM number: 106300
Dr. med. Kaimo Hirv
The HLA-B*27 typing is of clinical importance in association with ankylosing spondylitis (Bechterew's disease). Approximately 8% of the population carries the HLA-B*27 allel; approx. 1% of all carriers develop Bechterew's disease. Vice versa, the HLA-B*27 allel can be detected in 90% of all patients with Bechterew's disease. Therefore, HLA-B*27 currently represents the most important marker for ankylosing spondylitis. The German National Disease Management Guideline “Kreuzschmerz” (lower back pain) recommends HLA-B*27 typing in the case of chronic lower back pain with unknown cause and onset before 45 years of age. HLA-B*27 typing plays a key role in the detection of early forms of axial spondyloarthritis (ASAS criteria) in the absence of radiological evidence. Molecular subtyping of the HLA-B*27 characteristic allows the exact identification of persons who have a low risk of developing the disease or show a very mild and prolonged course of the disease despite positive immunologic detection of HLA-B*27. The HLA-B alleles *27:06, *27:07 and *27:09 show a markedly reduced disease association in contrast to the alleles *27:02, *27:04 und *27:05.