Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn’s disease (CD), is a chronic, idiopathic, debilitating, and currently incurable inflammatory gut disorder. It affects nearly 3 million people in the United States and 7 million worldwide, and its incidence is increasing globally. It also causes series of complications, including increased risk of colon cancer. Histopathology plays a critical role in establishing diagnosis, monitoring disease activity, evaluating medical treatment effect, assessing mucosal healing status, predicting relapse risk, and detecting neoplastic development in patients with longstanding disease. This presentation will describe the major histopathologic features of UC and CD as well as the associated precancerous mucosal lesions, discuss the current roles and challenges of histopathology in the clinical diagnosis and management of IBD, and highlight the major pathogenetic mechanisms of IBD.

After viewing this lecture, participants should be able to:
1. Identify the major histopathologic features of ulcerative colitis and Crohn’s disease and the various types of precancerous lesions associated with IBD.
2. Recognize the current role and challenge of histopathology in clinical diagnosis and management of patients with IBD.
3. Discuss the basic pathogenetic mechanisms of IBD and some tobeunderstood questions related to IBD pathology.

Xianyong (Sean) Gui, MD
Associate Professor, Anatomic Pathology
Department of Laboratory Medicine & Pathology
University of Washington

11/17/21