A Multiparametric Method Improves the Serological Characterization of Inflammatory Bowel Diseases: Preliminary Results from a Multicenter Eastern Europe Study

Introduction: The serological support to early diagnosis and differential diagnosis of inflammatory bowel diseases (IBD) is actually very limited. In this study we evaluated the performance of a promising multiparametric method including either well established and newly developed biomarkers. Methods: This multicenter retrospective observational study finally enrolled 156 patients with IBD, 100 affected by Crohn’s disease (CD) and 56 by ulcerative colitis (UC) recruited at the Gastroenterology Units of Udine (Italy), Rijeka (Croatia) and Belgrade (Serbia). Twently age-sex matched blood donors (BD) were included as controls. Autoantibody profiles were determined using a mosaic cell and tissue-based indirect immunofluorescence (IIF) method simultaneously investigating: anti-saccharomyces cerevisiae antibodies (ASCA), anti-atypical perinuclear neutrophilic antibodies (P-ANCA), anti-pancreatic antigens antibodies (PAB) and anti-goblet cells antibodies (GAB). Results: PAB (anti-CUZD1 and/or anti-GP2 antibodies) were present in 24 CD patients versus none of UC patients or BD (24% sensitivity, 100% specificity). As regards CD patients, combined positivity of PAB and ASCA (sensitivity 84%, specificity 71.4%) performed better than ASCA alone. Colon involvement (87.5% vs. 60.5%; p=0.014), deep mucosal lesions (58.3% vs. 25.0%; p=0.002) and need for biologic therapies (79.2% vs. 46.1%; p=0.005) were significantly more prevalent in PAB-positive than in PAB-negative CD patients. Multivariate analysis identified PAB positivity (OR=3.67; 95%CI=1.29-10.46) and anti-CUZD1 in particular (OR=3.54; 95%CI=1.08-11.63) as significant risk factors for deep mucosal lesions development in CD. Conclusion: A multiparametric diagnostic approach appears very useful to better characterize IBD patients. PAB, isolated or combined with other autoantibodies, may support both differential diagnosis and selection of CD patients at risk for more severe disease.