P351 Faecal calprotectin correlates well with extent of active endoscopic inflammation in patients with ulcerative colitis
D. Chayut1, M. Kaplan2, Y. Chowers3, M. Waterman*3
1The Technion - Israel Institute of Technology, B. Rappaport Faculty of Medicine, Haifa, Israel, 2Rambam Health Care Campus, Department of Laboratory Medicine, Haifa, Israel, 3Rambam Health Care Campus, Department of Gastroenterology, Haifa, Israel
Faecal calprotectin (FC) is a non-invasive marker of inflammation activity in patients with ulcerative colitis (UC) and correlates well with the severity of inflammation as found during colonoscopy. The correlation between FC levels and the endoscopic extent of involvement has been less well investigated in adults with UC. Aim: to explore the role of FC in predicting the endoscopic extent of colonic involvement in UC patients
UC patients who underwent endoscopy within 3 months of FC collection were included. Clinical (age, gender, therapy type, partial Mayo score [PMS]) and endoscopic markers were collected using retrospective chart review. FC was determined using the Quantitative Lateral Flow Assay, (Buehlmann, Schönenbuch, Switzerland). Initially the 30–300 µg/gr range assay was used and, when initial test was > 300 µg/gr, then the 100–1 800 range test was used. Endoscopic grading of inflammation were measured using the endoscopic Mayo score for inflammation severity (1 = mild, 2 = moderate, 3 = severe) and the Montreal classification for inflammation location (L1 = proctitis, L2 = left colitis, L3 = proximal colitis). For correlation assessment FC results were grouped to 3 groups: < 300, 300–1 800, >1 800. Correlation was analysed using the Spearman Correlation index (SPSS). Linear regression model using the PMS, rectal bleeding score and continuous FC results measures was constructed to improve correlations.
In total, 40 patients with endoscopy assessment and FC results were included. Of the patients, 45% were females; mean diagnosis age was 37 years; topical therapy alone or in combination was given to 15 (38%) patients, and 22.5%, 10%, and 15% received corticosteroids, thiopurines, and biologics, respectively. The PMS was 0–3, 4–6, and 7–9 in 18 (45%), 11 27.5%) and 11 (27.5%) of patients, respectively. Low (0–300), moderate (300–1 800), and high FC (>1 800) was measured in 22 (55%), 7 (17.5%), and 11 (27.5%) patients, respectively. Good correlation was seen with inflammation location (ρ = 0.518, p = 0.001; Figure1A) but not with the endoscopic severity score (ρ = 0.258, p = 0.104, Figure1B). Linear regression model using disease location and calprotectin score as continuous variables and incorporating rectal bleeding score and Mayo partial clinical score improved location prediction with R2 = 0.68.
Figure 1. A and B Correlation of faecal calprotectin with inflammation extent and severity.
FC is reasonably accurate in predicting active disease location. This may be improved by adding clinical markers such as rectal bleeding and PMS. Pending larger studies validation, FC may be useful to direct topical vs systemic therapy in UC.