P308 A new endoscopic scoring system corresponding to histological healing using linked color imaging in ulcerative colitis: SOUL study

Abstract

Abstract Background An important therapeutic aim in ulcerative colitis (UC) is endoscopic remission. Although an endoscopic score with white light imaging (WLI) is mainly used to evaluate endoscopic findings, recently, the usefulness of linked color imaging (LCI) has been reported. We evaluated the relationship between LCI and histopathological findings and attempted to establish a new LCI endoscopic evaluation index for UC. Methods This study was conducted at Kyorin University, Kyoto Prefectural University, and Fukuoka University Chikushi Hospital. Ninety-two patients (median age, 46 years; male/female ratio, 48/34) with a Mayo endoscopic subscore (MES) ≤1 who underwent colonoscopy for UC in clinical remission between November 2016 and January 2019 were included. LCI index was defined as degree of redness (R) (grade 0–2), area of inflammation (A) (grade 0–3), and visibility of lymphoid follicles (L) (grade 0–3). Endoscopic scores were determined by three central endoscopic judgment committee members who are experts in colonoscopy for UC. Discussions were held among the three members, and when two or more of them had the same judgment this was adopted as the final evaluation. Each biopsy was performed from an identical site of colonoscopic image. Histological healing was defined as Geboes score <2B.1. Histopathological scores were also determined by central judgment. Results In 92 patients, 85 biopsies from the sigmoid colon and 84 biopsies from the rectum (total 169 biopsies) were evaluated. Percentage of judgments that were consistent in two or more central endoscopic judgment committee members were 167/169 (98.8%) cases in MES, 164/169 (97.0%) cases in LCI index-R, 152/169 (89.9%) cases in LCI-index-A, and 150/169 (88.8%) cases in LCI-index-L. Regarding the κ-score in diagnosing by the two pathologists, “Chronic inflammatory infiltrate”, “Crypt destruction”, and “Crypt destruction” had a moderate agreement, and others had a stationary agreement. The overall histological healing rate was 84.0% (142/169). There were 22/117/30 cases of grade 0/1/2 in LCI index-R, 113/34/17/5 cases of grade 0/1/2/3 in LCI index-A, and 124/27/14/4 cases of grade 0/1/2/3 in LCI index-L. Histological healing was achieved in 84.1% (142/169) of the cases, and there were significant associations with histological healing/non-healing in LCI index-R (P=0.013) and A (P=0.0014). Conclusion A new LCI index is useful for predicting histological healing in UC patients with MES ≤1 and clinical remission.