Correlation Between Fecal Biomarkers and the Presence of Antineutrophil Cytoplasmic Antibodies with Ulcerative Colitis Disease Activity

Abstract

Background Although colonoscopy remains the gold standard for Ulcerative colitis (UC) diagnosis due to its invasive and costly nature, non-invasive biomarkers are gaining importance in disease activity monitoring and diagnosis. In our study, we aimed to evaluate the correlation of fecal calprotectin (FC) and fecal lactoferrin (FL) levels with the disease activity according to 3 different disease activity indices and to investigate the relationship between the presence of peri-nuclear anti-neutrophil antibody (p-ANCA) and disease activity.Methods Our study was planned as a prospective cohort study and 80 patients diagnosed with UC who were admitted to the Gastroenterology department between 01.05.2023 and 01.09.2023 at Ondokuz May & imath;s University Hospital were included in the study. 'Truelove and Witts' (TLW) activity index, SEO index and Mayo Score were applied. FC and FL levels in stool samples were analysed by Enzyme-Linked ImmunoSorbent Assay (ELISA), while p-ANCA presence in blood samples was examined using the Indirect Immunofluorescent Antibody (IIFA) method.Results It has been demonstrated that both faecal biomarkers can distinguish severe disease, but according to ROC analysis, the discriminatory power of FC is higher than that of FL. The cutt-off values calculated for severe disease were found above 300 mu g/g for FC and above 130 mu g/g for FL. Also ANCA positivity and formalin-resistant ANCA positivity in the severe disease group were statistically higher than mild disease group.Conclusions In addition to the relationship between faecal biomarkers and disease activity, our results demonstrated that patients with severe disease exhibited high rates of ANCA positivity and formalin resistance.