Laurent, V.

Abstract Background and Aims Intestinal ultrasound (IUS) is increasingly used to monitor treatment efficacy in inflammatory bowel disease (IBD) trials. However, standardized definitions for response, remission, and optimal assessment timing remain undefined. An international expert consensus meeting was held to establish IUS endpoints for clinical trials. Methods A panel of 35 international gastroenterologists and radiologists participated in a modified Delphi process, reviewing the literature and developing consensus statements. Agreement was defined as at least 75% consensus. Results Consensus was reached on 150 statements across four domains: general IBD (30 statements), luminal Crohn’s disease (CD) (43), perianal CD (51), and ulcerative colitis (UC) (26). For luminal CD and UC, ultrasound response was defined by: (1) a ≥25% reduction in bowel wall thickness (BWT) from baseline, or (2) multifactorial improvement, combining BWT reduction with ≥1 grade decrease in color Doppler signal (CDS) or another IUS parameter. Assessments were set at weeks 4-8 for the colon and week 12 for the terminal ileum. Ultrasound remission in luminal CD was defined as: (1) BWT normalization (≤3 mm) or (2) normalization of multiple parameters, including BWT, CDS, and all other IUS parameters. Similar remission criteria were proposed for UC, but the sigmoid BWT normal range (3-4 mm) remained uncertain. The bowel ultrasound score (BUSS) for CD and the Milan ultrasound criteria (MUC) for UC were supported as standardized scoring systems for trials. Conclusion This consensus provides standardized IUS definitions to enhance consistency in IBD trials, supporting the integration of IUS in future research.

SummaryBackgroundReliable tools for patient selection are critical for clinical drug trials.AimTo evaluate a consensus‐based, standardised magnetic resonance enterography (MRE) protocol for selecting patients for inclusion in Crohn's disease (CD) multicenter clinical trials.MethodsThis study recruited 20 patients [Crohn's Disease Activity Index (CDAI) scores: <150 (n = 8); 150–220 (n = 4); 220–450 (n = 8)], to undergo ileocolonoscopy and two MREs (with and without colonic contrast) within a 14‐day period. Procedures were scored centrally using, Magnetic Resonance Index of Activity (MaRIA), and both Crohn's Disease Endoscopic Index of Severity (CDEIS) and Simplified Endoscopic Score (SES‐CD).Results37 MREs were acquired. Both MREs were evaluable in 16 patients for calculation of test–retest and inter‐reader reliability scores. The MaRIA scores for the terminal ileum had excellent test–retest and inter‐reader reliability, with correlations >0.9. The proximal ileum showed strong within‐reader agreement (0.90–0.96), and fair between‐reader agreement (0.59–0.72). MRE procedures were tolerable. MaRIA scores correlated with CDEIS and SES‐CD (0.63 and 0.71), but not with CDAI (0.34). MRE identified 3 patients with intra‐abdominal complications, who would otherwise have been included in clinical trials. Furthermore, both MRE and ileocolonoscopy identified active bowel wall inflammation in 2 patients with CDAI <150, and none in 1 patient with CDAI > 220. Data quality was good/excellent in 85% of scans, and fair or better in 96%.ConclusionsMagnetic resonance enterography of high‐quality and reproducibility was feasible in a global multi‐ centre setting, with evidence for improved selectivity over CDAI and ileocolonoscopy in identifying appropriate CD patients for inclusion in therapeutic intervention trials.