Ultrasound remission after biologic induction and long-term endoscopic remission in Crohn's disease: a prospective cohort studyResearch in context

Summary: Background: The Bowel Ultrasound Score (BUSS) accurately detects therapy-related changes by using the Simple Endoscopic Score for Crohn's disease (SES-CD) as the reference standard. We aimed to evaluate ultrasound remission as a treatment target and its prediction for long-term endoscopic remission. Methods: This single-centre prospective observational study, based at a tertiary referral centre in Milan, Italy, enrolled, between March 1, 2018, and January 31, 2021, adult patients with active CD (SES-CD >2) who were starting biologics. Colonoscopy and IUS was performed at baseline and at 12 months (mean 12.8 ± 4.2). The primary outcome was the predictive value of ultrasound remission at week 12 (BUSS ≤3.52) for long-term endoscopic remission at 12 months. The International Bowel Ultrasound Segmental Activity Score (IBUS-SAS) was also calculated and optimal cut-point to detect endoscopic remission was identified through ROC analysis. Findings: 93 patients with CD were included. Of these, 22 patients (24%) achieved endoscopic remission. Week 12 ultrasound remission predicted endoscopic remission (59% compared with 41% of the patients who were not in ultrasound remission; OR 9.93, 95% CI 3.10–31.80; p