Intestinal Ultrasound-Guided Precision Medicine in Inflammatory Bowel Diseases: A Narrative Review.

Inflammatory bowel diseases (IBD), including Crohn's disease and ulcerative colitis, are characterized by marked heterogeneity, challenging disease monitoring and individualized treatment. Despite advances in treat-to-target strategies, unmet needs persist, particularly in assessing transmural healing and optimizing therapeutic decisions. This narrative review evaluates the role of intestinal ultrasound (IUS) as a key tool for precision medicine in IBD. IUS is a non-invasive, repeatable, and cost-effective imaging modality with diagnostic accuracy comparable to endoscopy and magnetic resonance enterography, with reported sensitivities and specificities frequently exceeding 80-90% for detecting active disease. It enables real-time assessment of transmural inflammation and complications, while parameters such as bowel wall thickness and Doppler vascularity support prognostic stratification. Early reductions in bowel wall thickness (≥25-30%) have been associated with improved treatment response, allowing identification of responders within weeks of therapy initiation. IUS informs therapeutic decision-making, including initiation, optimization, and de-escalation of advanced therapies, and may reduce reliance on invasive procedures. Integration into routine care has been associated with improved disease control and cost-effectiveness. Standardization of protocols, operator training, and prospective validation are required to establish IUS as a cornerstone of precision medicine in IBD.