Histologic evaluation of disease activity in inflammatory bowel disease

Histologic examination of the gastrointestinal (GI) tract plays an essential role in the diagnosis and differential diagnosis of inflammatory bowel disease (IBD). With the availability of more potent anti-IBD therapies and subspecialization of GI pathology, the evaluation of GI specimens either biopsy or resection specimens from patients suspicious for IBD or IBD patients suffering from disease relapse or in surveillance, becomes more detail-oriented. The benefit of histologic mucosal healing in the clinical outcome of patients with ulcerative colitis (UC) has emerged calling for a tiered, precise, and reliable scoring system in IBD pathology practice. This chapter is to review the previously published histopathology scoring systems in UC and Crohn’s disease and the daily pathology practice pattern in IBD care. As a thorough histologic assessment of IBD activity is time-consuming, how to achieve a cost-effective histologic evaluation of IBD specimens to meet the ever-increasing clinical demands remains a challenge.