Abstract
BACKGROUND AND AIMS: Though colonoscopy plays a crucial role in assessing active ulcerative colitis [aUC], its scope is limited to the mucosal surface. Endoscopic ultrasound [EUS] coupled with contrast-enhancement [dCEUS] can precisely quantify bowel wall thickness and microvascular circulation, potentially enabling the quantitative evaluation of inflammation. We conducted a prospective, longitudinal study to assess therapy response using dCEUS in aUC patients undergoing treatment with adalimumab [ADA] or infliximab [IFX]. METHODS: Thirty ADA- and 15 IFX-treated aUC patients were examined at baseline and at 2, 6, and 14 weeks of therapy and 48 weeks of follow-up. Bowel wall thickness [BWT] was measured by EUS in the rectum. Vascularity was quantified by dCEUS using rise time [RT] and time to peak [TTP]. Therapy response was defined after 14 weeks using the Mayo Score. RESULTS: Patients with aUC displayed a mean BWT of 3.9 ± 0.9 mm. In case of response to ADA/IFX a significant reduction in BWT was observed after 2 weeks [p = 0.04], whereas non-responders displayed no significant changes. The TTP was notably accelerated at baseline and significantly normalized by week 2 in responders [p = 0.001], while non-responders exhibited no significant alterations [p = 0.9]. At week 2, the endoscopic Mayo score did not exhibit any changes, thus failing to predict treatment responses. CONCLUSION: dCEUS enables the early detection of therapy response in patients with aUC, which serves as a predictive marker for long-term clinical success. Therefore, dCEUS serves as a diagnostic tool for assessing the probability of future therapy success.