Spondylarthrite Ankylosante Risk Factors

Genetic Risk Factors

The presence of HLA-B27 confers a high relative risk of developing ankylosing spondylitis, with a prevalence of 74-89% in patients with the disease, according to the American College of Rheumatology 1
HLA-B27 is present in 25-75% of patients with inflammatory bowel disease who develop ankylosing spondylitis, as reported by the European Crohn's and Colitis Organisation 2

The onset of symptoms typically occurs before the age of 40-45 years, with an insidious onset characteristic of inflammatory back pain, as noted by the American College of Rheumatology 1
Age of onset before 45 years is a distinctive feature of inflammatory back pain associated with ankylosing spondylitis, according to the American College of Rheumatology 1

Inflammatory bowel disease is associated with an increased risk of developing ankylosing spondylitis, with 25-75% of patients with inflammatory bowel disease who develop ankylosing spondylitis being HLA-B27 positive, as reported by the European Crohn's and Colitis Organisation 2 and the American College of Rheumatology 1

Uveitis (ocular inflammation) is a common extra-articular manifestation that can precede or accompany ankylosing spondylitis, as noted by the American College of Rheumatology 1
Psoriasis is associated with axial spondyloarthritis, according to the American College of Rheumatology 1
Peripheral arthritis affecting large joints (notably the knees) in an oligoarticular asymmetric pattern occurs in 30-50% of patients, as reported by the American College of Rheumatology 1