P492 All intestinal ultrasound scores for ulcerative colitis (and IBUS-SAS) strongly correlate with endoscopic activity: a prospective study

Abstract

Abstract Background Intestinal ultrasound (IUS) is gaining increasing acceptance as a reliable tool for tight monitoring of ulcerative colitis (UC). Although several IUS scores have been proposed, none has been formally implemented into official recommendations of international scientific societies. This study aims to compare the available IUS score for UC, in terms of correlation with endoscopic activity. Methods Patients with UC ≥ 18 years old undergoing partial or full colonoscopy between April and October 2023 were prospectively included. Endoscopic evaluation of at least the sigmoid colon was mandatory for inclusion, and patients with proctitis (Montreal E1) were excluded. Endoscopic activity was scored with both the Mayo Endoscopic Subscore (MES) and the Ulcerative Colitis Endoscopic Index of Severity (UCEIS), and defined by MES ≥ 1 and UCEIS ≥ 2. IUS was performed within 4 weeks of endoscopy. The Milan Ultrasound Criteria (MUC, Allocca et al.), the UC-IUS score (Bots et al.), the US Score from Parente et al., and the score from Hata et al. were included in the analysis. Applicability of the US Score from Civitelli et al, an IUS score developed for paediatric patients, and the IBUS-SAS, an IUS score validated for Crohn’s disease, was also evaluated. The Spearman’s rank coefficient (rho = ρ) was used to perform correlations, while receiver operating characteristic (ROC) curves were compared with the Hanley & McNeil method. Results Fifty-nine patients were included, of which 59.3% and 50.8% showed any endoscopic activity using the MES and the UCEIS, respectively. Detailed information about the population is reported in Table. All the evaluated IUS scores showed a significant positive correlation with endoscopic activity (p < 0.001), with the UC-IUS score and the US Score from Civitelli et al. outperforming the others both with MES (ρ = 0.745, ρ = 0.762) and UCEIS (ρ = 0.751, ρ = 0.769). The same scores showed the highest Areas Under the Curve (AUC) for detecting a MES ≥ 2 (UC-IUS: 0.841, 95%CI 0.722-0.923, p < 0.001; Civitelli et al.: 0.842, 95%CI 0.724-0.924, p < 0.001) [Figure]. The optimal cut-offs for detecting a MES ≥ 2 with both the MUC and the Civitelli score were similar to that proposed by the Authors (> 5.04 vs > 6.20 and > 2 vs > 1, respectively). Conclusion All the included IUS scores showed good correlation with endoscopic activity. The UC-IUS and the US Score from Civitelli et al. performed better than the others in detecting a MES ≥ 2 and might be suggested to monitor disease activity of UC and intervene early during disease relapse.