Spondyloarthropathy is underestimated in inflammatory bowel disease: Prevalence and HLA association

Objective. To determine the overall prevalence of spondyloarthropathy (SpA) among patients with inflammatory bowel disease (IBD) [Crohn's disease (CD) and ulcerative colitis (UC)]. Methods. One hundred three consecutive patients with IBD from a gastroenter ology unit were questioned and examined for SpA symptoms. Patients previous ly diagnosed with SpA were excluded. All patients were questioned and exami ned for SpA symptoms such as inflammatory back pain, joint swelling, enthes itis, and psoriasis or a specific family history. Radiographs were taken of all sacroiliac joints. HLA loci A, B, C, and DR were determined in all pat ients. Results. Thirty-nine percent of the patients with IBD had clinical articula r manifestations: 30% had inflammatory back pain, 10% had synovitis, and 7% had a peripheral enthesopathy. The majority (90%) of patients with rheumat ic complaints fulfilled the classification criteria for SpA and 10% fulfill ed the criteria for ankylosing spondylitis. Asymptomatic sacroiliitis was f ound in an additional 18% of the patients. Moreover, sacroiliitis, symptoma tic or asymptomatic, was related to the disease duration. HLA-B27 conferred an additional risk for inflammatory low back pain in patients with IBD, Conclusion. Articular involvement in IBD can be classified as SpA, The appe arance of SpA occurs irrespective of the extent of the bowel disease. Moreo ver, asymptomatic sacroiliac involvement is a common manifestation in IBD a nd it is related to disease duration, suggesting evidence for a related pat hogenic mechanism.