The predictive value of intestinal ultrasound for treatment response in inflammatory bowel disease: a systematic review and pooled data analysis

INTRODUCTION: Intestinal ultrasound (IUS) is a promising tool for predicting treatment response in inflammatory bowel disease (IBD). We aimed to systematically review existing literature on the predictive value of IUS for treatment response. METHODS: A literature search was performed until May 2025. We included articles assessing treatment response in IBD using IUS. Data were analyzed separately for Crohn's Disease (CD), ulcerative colitis (UC) and acute severe ulcerative colitis (ASUC). Pooled data analysis was performed for bowel wall thickness (BWT) in CD patients starting anti-TNF (tumor necrosis factor). RESULTS: In total, 31 articles were included (18 CD, 9 UC, and 4 ASUC). In 8/10 CD studies, IUS at week 4-8 could distinguish future responders, with BWT change ranging from -43% to -14.6% in responders vs. -14% to + 2% in nonresponders. In the pooled data analysis of anti-TNF-treated CD patients (n = 236) a 23% decrease from baseline at week 4-8 (area under the receiver operating characteristic curve [AUROC] 0.82) and 27% decrease at week 12-16 (AUROC 0.78) could predict future response. In 2/2 UC studies, IUS after 4-8 weeks could predict future endoscopic remission vs. non-remission with a decrease in BWT ranging from -55% to -49% vs. -38% to -17% respectively. In ASUC, change in BWT after 1-3 days could predict need for salvage therapy (-34% vs. -10%). CONCLUSIONS: Intestinal ultrasound predicts response at an early stage after treatment initiation, both in CD as well as in UC. In anti-TNF-treated CD patients, 23% and 27% decrease in BWT after 4-8 weeks and 12-16 weeks of treatment initiation predicts outcomes.