Written by Chris Thom
Spoon Feed
This prospective study of Crohn’s disease patients showed a high correlation between point-of-care intestinal ultrasound (IUS) and ileo-colonoscopy.
Ultrasound correlates with active disease on endoscopy
This was a single-center study involving Crohn’s disease patients who received a point-of-care IUS and a subsequent ileo-colonoscopy within 1 week. A single ultrasound operator performed the IUS examinations. Findings evaluated on IUS included bowel wall thickness (BWT), color doppler signals, inflammatory fat (i-fat), and bowel wall stratification.
254 patients were enrolled in the study, with 170 of those having active disease upon ileo-colonoscopy. Average BWT on IUS for patients with no inflammation on colonoscopy was 2.09 mm. Mean BWT in patients with mild, moderate, and severe disease activity was 4.7, 5.2, and 6.3 mm. BWT of > 3 mm had a 96% sensitivity and 87% specificity for inflammation on colonoscopy. Color doppler findings of inflammation had a sensitivity of 96% and specificity of 91%, while the presence of i-fat had a sensitivity of 96% and specificity of 90%. i-fat was strongly associated with moderate to severe disease activity (OR 33.3, 95%CI 13.3-83.7). Lastly, 15 patients had IUS findings of disease activity in the small bowel in areas that were beyond the reach of ileo-colonoscopy.
How will this change my practice?
I often find myself equivocating over whether a patient I am seeing in the ED truly warrants CT imaging for a Crohn’s related complaint. These patients are often young and have a pre-existing high burden of ionizing radiation, yet are at risk for active inflammatory disease. While the clinic study setting precludes definite conclusions in other patient settings, it does spark interest that POCUS could potentially play a role in the future. The presence of bowel wall thickening is often easy to identify on POCUS, and perhaps a reassuring POCUS could lead to avoidance of a CT, while a more pathological POCUS portends the need for one. Time will tell.
POCUS pro-tips and clips
Normal bowel wall is very thin and can be difficult to accurately measure. As the bowel wall thickens, it will become much easier to see and to measure. Survey the bowel over the area of maximal tenderness, as this can be the highest yield on a reliable patient. Like many topics with POCUS, it helps to see several normal cases before trying to interpret abnormal. I find the presence of inflammatory fat very helpful in many scenarios, including colitis, appendicitis, and enteritis. As in this study, the OR of active inflammation goes up significantly with this finding. Look for hyperechoic areas within the intraabdominal fat tissue and adjacent to the bowel loops. Although it does require some pattern recognition, this skill is immensely valuable to learn and become proficient in.
Source
Correlation of Point-of-Care Intestinal Ultrasound With Endoscopic Disease Severity in Crohn’s Disease. JGH Open. 2025 Jul 31;9(8):e70231. doi: 10.1002/jgh3.70231. PMID: 40747353; PMCID: PMC12311311.
