Abstract Background This study aimed to evaluate intestinal ultrasound (IUS) findings in ulcerative colitis (UC) patients with endoscopic remission (ER) and to investigate the clinical characteristics and treatment-related factors associated with the presence of ultrasonographic activity. Methods Mayo endoscopic score of 0 and 1 were ER. Patients with ER were scheduled for IUS within 3 to 14 days. IUS was performed using a standardized protocol by a single gastroenterologist certified by the International Bowel Ultrasound Group (IBUS). For each intestinal segment, two longitudinal and two cross-sectional measurements of bowel wall thickness (BWT) were obtained. Colour Doppler signal intensity, bowel wall stratification, and mesenteric fat inflammation were scored according to the IBUS Segmental Activity Score (IBUS-SAS) (1) IUS activity was assessed using IBUS-SAS score (1), Milan Ultrasound Criteria (MUC) (1), and UC-IUS scores (3). The IUS activity scores were calculated using a web-based platform (available at [https://ibduscore.com). Additionally, BWT (≥ 3 mm) was also assessed as an independent IUS activity, without requiring any additional ultrasonographic criteria. Results Among 35 patients in endoscopic remission (Mayo 0: n = 23; Mayo 1: n = 12), ultrasonographic activity was detected in 2.9% by MUC, 31.4% by IBUS-SAS, 17.1% by UC-IUS, and 22.8% based on BWT alone (Table 1). A substantial and statistically significant agreement was observed between IBUS-SAS and MUC (Kappa = 0.706, p 0.001). A moderate and statistically significant agreement was observed between IBUS-SAS and BWT positivity (BWT ≥3 mm) (Kappa = 0.559, p = 0.001). A substantial agreement was observed between BWT positivity and MUC (Kappa = 0.643, p 0.001). Longer disease duration, being on biologic therapy and longer biologic treatment duration were more frequent among patients with IUS activity without statistical significance (Table 2). Among patients with intestinal ultrasound–based evidence of disease activity, the mean albumin level was 4.5 ± 0.528 g/dL. Conclusion Despite endoscopic remission, nearly 30% of UC patients have ultrasonographic signs of residual inflammation, when assessed by IBUS-SAS score. Although mucosal healing remains the primary therapeutic goal, persistent ultrasonographic activity in some UC patients may warrant consideration in ongoing therapeutic planning. References: 1. Fischer S, Fischmann D, Wilde J, et al. IBUS-SAS Is a Highly Accurate Intestinal Ultrasound Score for Predicting Endoscopic Disease Activity in Ulcerative Colitis. United European Gastroenterol J. 2025;13(7):1253-1262. doi:10.1002/ueg2.70053 2. Allocca M, Filippi E, Costantino A, et al. Milan ultrasound criteria are accurate in assessing disease activity in ulcerative colitis: external validation. United European Gastroenterol J. 2021;9(4):438-442. doi:10.1177/2050640620980203 3. Bots S, Nylund K, Löwenberg M, Gecse K, D’Haens G. Intestinal Ultrasound to Assess Disease Activity in Ulcerative Colitis: Development of a novel UC-Ultrasound Index. J Crohns Colitis. 2021;15(8):1264-1271. doi:10.1093/ecco-jcc/jjab002 Conflict of interest: Dr. Eskazan, Tugçe: No conflict of interest Ceylan, Gokce: No conflict of interest Alasgarlı, Subhana: No conflict of interest Kati, Okan: No conflict of interest Akpınar, Atilla: No conflict of interest Bakkaloglu, Oguz Kagan: No conflict of interest Erzin, Yusuf Ziya: No conflict of interest Çelik, Aykut Ferhat: No conflict of interest Hatemi, Ali Ibrahim: No conflict of interest
Eşkazan et al. (Thu,) studied this question.