Beyond the mucosa: The emerging role of endoscopic ultrasound in the diagnosis and management of inflammatory bowel disease

Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are chronic immune-mediated conditions of the gastrointestinal tract. Accurate diagnosis, disease monitoring, and prediction of treatment response remain major challenges. Endoscopic ultrasound (EUS), originally developed for pancreatobiliary indications, offers high-resolution, transmural imaging and is gaining relevance in IBD assessment. This review comprehensively examines the emerging applications of EUS in IBD, including its potential role in diagnosis, in distinguishing CD from UC, in evaluating disease activity and predicting clinical outcomes and therapeutic responses to biologic agents, through parameters such as bowel wall thickness, parietal stratification, vascular patterns and lymphadenopathy. EUS also enables detailed evaluation and characterization of colorectal lesions and supports real-time, minimally invasive therapeutic interventions, including drainage of intra-abdominal fluid collections, management of perianal fistulas, and guidance during endoscopic dilation of strictures. Technological advancements like contrast-enhanced EUS, elastography, and through-the-scope mini-probes have further enhanced diagnostic accuracy and procedural versatility. While promising, widespread adoption of EUS in IBD management is limited by the need for standardized protocols and adequate training. Nonetheless, ongoing technological developments and integration with artificial intelligence are expected to expand its role in precision medicine, ultimately improving patient outcomes through better disease characterization, monitoring, and individualized therapeutic strategies.