PMO-45 Faecal calprotectin, an alternative marker to estimate cumulative inflammatory burden in Ulcerative Colitis

IntroductionLong-term Ulcerative Colitis (UC) increases the risk of colonic dysplasia and colorectal cancer (CRC). We aim to establish whether real-world faecal calprotectin (FCP) data can be used to estimate the cumulative inflammatory burden (CIB) and identify those at risk of dysplasia and CRC.MethodsPatients with left sided or extensive UC of >8 yrs duration, with >1 endoscopy and >1 serial FCP value (from 2005) were extracted from the NHS Lothian IBD registry. Patients with PSC were excluded.CIB scores based on histology (CIB(H)) or FCP (CIB(FCP)) were calculated based on the method proposed by Choi et al [1]. Patients were categorised into three groups; IBD-associated dysplasia and CRC (IBD-D/CRC n=15), only sporadic adenomas (n=29, excluded from further analysis) and patients who did not develop any type of dysplasia (n=220).To give a more accurate estimation of cumulative inflammation FCP levels were defined as low (n=73) or high (n=162). High CIB(FCP) is equivalent to 5 yrs of a continuous FCP value of ≥250µg/g, a surrogate marker of chronic active inflammation.ResultsA defined cohort of 264 patients (146 males), with a median age 36 (IQR 27.1-46.9) were included.Using the CIB(H) score, patients with no dysplasia (n=220) had a median score of 4.7 (IQR 2.7-7.9), compared with patients with IBD-D/CRC (n=15) who had a score of 5.4 (3.5-8.2) (p=0.4405, unpaired two-tailed t-test).The median CIB (FCP) score for patients with no dysplasia was 1804 (883-3689), compared with patients with IBD-D/CRC who had a median score of 2256 (1593-3848) (p=0.4835). The correlation between the two types of CIB scores in identifying risk of IBD-D/CRC was weak (Spearman’s rho=0.296 (p