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

Abstract

Objectives 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, 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 with a Mayo endoscopic subscore (MES) ≤1 who underwent colonoscopy for UC in clinical remission were included. LCI index was defined as redness (R) (grade 0–2), area of inflammation (A) (grade 0–3), and lymphoid follicles (L) (grade 0–3). Histological healing was defined as Geboes score <2B.1. Endoscopic and histopathological scores were 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. 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 84.0% (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). Conclusions A new LCI index is useful for predicting histological healing in UC patients with MES ≤1 and clinical remission.