What HLA occurs more commonly than expected in patients with inflammatory spinal arthritis associated with IBD?
- HLA-B27 is found in 55% of CD patients and 70% of UC patients with inflammatory sacroiliitis or spondylitis.
- This contrasts with an 8% frequency of HLA-B27 in a normal, healthy, white population.
- Thus a patient with IBD who possesses the HLA-B27 gene has 7 to 10 times increased risk of developing inflammatory sacroiliitis or spondylitis compared with IBD patients who are HLA-B27 negative.
