Intestinal ultrasound in inflammatory bowel disease: a valuable and increasingly important tool

Background: Intestinal ultrasound is emerging as a non-invasive tool for monitoring disease activity in inflammatory bowel disease patients due to its low cost, excellent safety profile, and availability. Herein, we comprehensively review the role of intestinal ultrasound in the management of these patients. Summary: Intestinal ultrasound has a good accuracy in the diagnosis of Crohn's disease, as well as in the assessment of disease activity, extent, and evaluating disease-related complications, namely strictures, fistulae, and abscesses. Even though not fully validated, several scores have been developed to assess disease activity using ultrasound. Importantly, intestinal ultrasound can also be used to assess response to treatment. Changes in ultrasonographic parameters are observed as early as 4 weeks after treatment initiation and persist during short- and long-term follow-up. Additionally, Crohn's disease patients with no ultrasound improvement seem to be at a higher risk of therapy intensification, need for steroids, hospitalisation, or even surgery. Similarly to Crohn's disease, intestinal ultrasound has a good performance in the diagnosis, activity, and disease extent assessment in ulcerative colitis patients. In fact, in patients with severe acute colitis, higher bowel wall thickness at admission is associated with the need for salvage therapy and the absence of a significant decrease in this parameter may predict the need for colectomy. Short-term data also evidence the role of intestinal ultrasound in evaluating therapy response, with ultrasound changes observed after 2 weeks of treatment and significant improvement after 12 weeks of follow-up in ulcerative colitis. Key Messages: Intestinal ultrasound is a valuable tool to assess disease activity and complications, and to monitor response to therapy. Even though longer prospective data are warranted, intestinal ultrasound may lead to a change in the paradigm of inflammatory bowel disease management as it can be used in a point-of-care setting, enabling earlier intervention if needed.