P138 Novel serum markers for predicting disease activity in ulcerative colitis: results from a retrospective case-control study

Abstract

Abstract Background Commonly used serum or faecal markers, such as C-reactive protein (CRP) and feacal calprotectin have several limitations and do not always correlate well with the degree of mucosal inflammation in the intestine as established by endoscopy. The aim of the current study was to evaluate the utility of a panel of serum markers (Visfatin, serum amyloid, LRG1, MMP-1, MMP-2, TFF3, Lipocalin-2 (NGAL), IL-6, IL-4, IL-7, IL-17) in predicting mucosal inflammation in ulcerative colitis(UC) patients. Methods We conducted an unmatched case-control retrospective study. Patients were selected consecutively, based on their enrollement date, from a prospective IBD cohort. We selected two groups of UC patients, each of them with active disease at baseline and different outcomes during follow-up: mucosal healing and persistant disease activity, as resulted from clinical and endoscopic evaluation. Inflammatory burden was investigated using the C-reactive protein and endoscopic activity was reported using the Mayo endoscopic score. Quality of life was also evaluated at each visit using The Short Inflammatory Bowel Disease Questionnaire (SIBDQ). Clinical disease activity was quantified using the partial Mayo score. Clinical remission was defined as a partial Mayo score < 2. Endoscopic activity was assessed using the Mayo endoscopic score[i] . Mucosal healing was defined as Mayo endoscopic score of 0. The selection of investigated biomarkers was based on the results of a systematic review previously published by the research team [i] State M, Negreanu L, Voiosu T, Voiosu A, Balanescu P, Mateescu RB. Surrogate markers of mucosal healing in inflammatory bowel disease: A systematic review. World J Gastroenterol. 2021 Apr 28;27(16):1828-1840. doi: 10.3748/wjg.v27.i16.1828. Results 84 serum samples from 42 patients were retrospectively analyzed (21 patients with mucosal healing and 21 patients with persistant activity during follow-up). Lipocalin proved to be a reliable marker for the noninvasive assessment of endoscopic activity, with 90% sensitivity and 95% specificity at a cut-off level of 0,421μg/ml (AUROC 0,677). The combination of lipocalin, age, gender and BMI (Figure 1) is a good predictor of persistant activity during follow-up (AUROC 0.87, 95% CI, 0.762-0.979). Conclusion Our findings provide support for the use of lipocalin as a surrogate marker for mucosal inflammation. The combination of lipocalin, age, gender and BMI might be useful for guiding treatment and monitoring decisions.