Intestinal Ultrasound Transmural Healing Was Associated With Improved Long‐Term Outcomes Among Patients With Endoscopic Remission: Results of a Prospective Study

Background STRIDE II guidelines recognise endoscopic healing as a main therapeutic target in Crohn's disease (CD). Nevertheless, transmural healing (TH) could reduce the risk of long‐term complications. Aim To assess the impact of intestinal ultrasound (IUS) TH on CD long‐term among patients with endoscopic healing. Method We conducted a prospective study of consecutive patients with CD who underwent colonoscopy with endoscopic healing (CDEIS < 4) and IUS. IUS TH was defined by a bowel wall thickness < 3 mm without colour Doppler signal. The primary endpoint was CD relapse (drug intensification, initiation of steroid, CD‐related hospitalization or surgery, luminal stricture/fistula or perianal CD). Results We included 93 patients. IUS TH was observed in 73%. No difference in median IBD‐risk score was observed among patients with and without IUS TH (22 (IQR 7–41) vs. 30 (IQR 13–55); p = 0.15). After a median follow‐up of 22.5 months (IQR 19.3–23.7), the cumulative risk of relapse was significantly lower among patients with IUS healing (17% vs. 48%; p = 0.007). The benefit of TH remained when considering only patients with complete endoscopic healing (CDEIS = 0) (12‐month relapse rate, 2% vs. 33%; p = 0.03). The risk of CD‐related hospitalization (3% vs. 16%; p = 0.04) and perianal CD (3% vs. 16%; p = 0.04) were significantly lower among patients with IUS healing. In multivariate analysis, the absence of TH remained the only independent factor associated with CD relapse (hazard ratio 2.6 (1.1–6.2); p = 0.03). Conclusion IUS TH was associated with improved long‐term outcomes with lower risks of CD relapse, hospitalization, and perianal CD.