Isolated Mild Hyperemia Identified by Intestinal Ultrasound Is Associated With Adverse Outcomes in Inflammatory Bowel Disease

ABSTRACT Background Increased bowel wall thickness (BWT) measured by intestinal ultrasound (IUS) is the most predictive sonographic parameter of endoscopic disease activity in Crohn's disease (CD) and ulcerative colitis (UC). The clinical significance of hyperemia in the absence of increased BWT has yet to be delineated. The aim of this study is to assess whether isolated hyperemia on IUS correlates with adverse disease outcomes (ADOs). Methods We conducted a retrospective cohort study of IBD patients who underwent IUS between 7/18/2022 and 5/7/2024. Patients with normal BWT (≤ 3.0 mm) + mild hyperemia (modified Limberg (mLimberg) 1) or no hyperemia (mLimberg 0) were included. Primary outcome was ADO within 12 months, defined as medication change or escalation, corticosteroid use, surgery, or hospitalization. Secondary outcome was the frequency of active disease by sonographic, endoscopic, or biochemical parameters within 12 months of the index IUS assessment. Additional secondary outcomes included the comparison of the frequency of ADOs between patients with mLimberg 1 in one bowel segment versus mLimberg 1 in two or three bowel segments on index IUS. Survival probabilities were compared using Kaplan–Meier analysis with log‐rank tests. Results 128 patients were included; 67 with mLimberg 1 (55 CD, 12 UC) and 61 with mLimberg 0 (52 CD, 9 UC). ADOs were seen in 3 months, 6, and 12 months in the mLimberg 1 versus the mLimberg 0 cohort in 28.4% versus 11.5%, 41.8% versus 24.6%, and 53.7% versus 31.1%, respectively ( p = 0.0166). The median time to ADO in the mLimberg 1 versus mLimberg 0 was 66.5 versus 136.5 days ( p = 0.017). Conclusion Isolated mild hyperemia on IUS is associated with ADOs and may warrant consideration in clinical decision‐making, treatment optimization, and future treat‐to‐target strategies.