Validation of screening criteria for spondyloarthritis in patients with inflammatory bowel disease in routine clinical practice.

BACKGROUND: Spondyloarthritis (SpA) is one of the most common extraintestinal manifestations of inflammatory bowel disease (IBD). Diagnostic delay must be avoided. AIMS: We assessed the validity of SpA screening criteria (any of the following characteristics: chronic low back pain with onset before 45 years of age; inflammatory lower back pain or alternating buttock pain; arthritis; heel enthesitis; dacylitis; HLA-B27 positivity; sacroiliitis on imaging). METHODS: This was a multicenter cross-sectional observational study in IBD patients aged ≥18 years. After evaluating the SpA screening criteria, the gastroenterologists referred the participants to the rheumatologists, who determined whether the patient fulfilled the screening criteria and carried out the necessary tests for SpA diagnosis. RESULTS: 35 (11.7%) out of 300 patients were diagnosed with SpA. The combination with the best balance between sensitivity and specificity (91.4% and 72.1%, respectively, when applied by the rheumatologists; 80% and 78.9%, when applied by the gastroenterologists) for SpA screening, was fulfillment of any of the following: chronic low back pain with onset before age 45 years, inflammatory low back pain or alternating buttock pain, arthritis, or dactylitis. CONCLUSION: This is one of the first studies to validate SpA screening criteria in IBD patients in routine clinical practice.