Clinical Utility of Intestinal Ultrasound for Guiding Therapy in Inflammatory Bowel Disease: A Retrospective Real-World Cohort from a Swiss Tertiary Center

Introduction: Inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), are chronic immune-mediated disorders that significantly impact patients' quality of life. Proper IBD management often requires invasive diagnostic procedures such as endoscopy. Transabdominal intestinal ultrasound (IUS) offers a promising alternative due to its noninvasive, inexpensive, and widely available nature. This study aimed to evaluate the effectiveness of IUS combined with clinical parameters in guiding treatment decisions for IBD patients in remission or relapse. Methods: This is a retrospective cohort study of University Hospital Zurich (January-August 2022), which included consecutive adult IBD patients undergoing a single transabdominal IUS for treatment decision-making. IUS influenced clinical decisions by guiding therapy continuation, modification, or cessation and addressing complications. Results: The study analyzed 103 consecutive IBD patients, 66% diagnosed with CD, and 34% with UC. The majority (69.9%) were in clinical remission, and two-third of the remission patients claimed also no symptoms (32% of the whole cohort were asymptomatic). Bowel wall thickness (BWT) in the terminal ileum and left colon also significantly influenced treatment decisions (p = 0.014 and p = 0.042, respectively). In a multivariable logistic regression, both diarrhea (p = 0.013) and maximal BWT (p = 0.020) remained statistically significant predictors for a change in treatment. Conclusion: The study demonstrates that IUS, along with clinical symptoms such as diarrhea, plays a significant role in guiding treatment decisions for IBD patients. Diarrhea and BWT were strong predictors for adjusting therapy, highlighting the value of integrating noninvasive imaging with clinical assessment to optimize IBD management.