Intestinal Ultrasound Findings and Their Prognostic Value in Early Crohn's Disease: A Copenhagen IBD Cohort Study

We characterize the sonographic features of Crohn's disease at diagnosis and evaluate the prognostic value of intestinal ultrasound during the early stage of disease.

A prospective, population-based cohort of patients with newly diagnosed Crohn's disease were followed with intestinal ultrasound in conjunction with symptomatic, biochemical, and endoscopic evaluations.

Between May 2021 and April 2023, 201 patients with adult-onset Crohn's disease were recruited. No associations were found between sonographic inflammation at diagnosis and diagnostic delay. After 3 months, transmural remission was achieved in 38% of patients, with patients with colonic disease achieving transmural remission more often. Transmural remission at 3 months was significantly associated with steroid-free clinical remission at 3 months and all subsequent follow-ups within the first year. Transmural remission was also associated with a lower risk of treatment escalation during follow-up until 12 months (26% vs 53%; P = .003). At 12 months, 41% had achieved transmural remission. Higher baseline body mass index negatively impacted the likelihood of 12-month transmural remission significantly (overweight: odds ratio [OR], 0.34; 95% confidence interval [CI],0.12-0.94; obese: OR, 0.16; 95% CI, 0.04-0.73). The International Bowel Ultrasound Segmental Activity Score (IBUS-SAS) in the terminal ileum at diagnosis was the best predictor of ileocecal resection during the first year, with an optimal threshold of 63 (area under the curve [AUC], 0.92; sensitivity, 100%; specificity, 73%).

Transmural remission is an achievable outcome target for many patients with newly diagnosed Crohn's disease and is associated with a favorable clinical outcome, including sustained steroid-free clinical remission. Further, intestinal ultrasound findings at diagnosis predict future ileocecal resection.