Crohn’s disease

Abstract

This is a chronic granulomatous inflammatory condition that can involve any part of the gastrointestinal tract. It may occur at any age, and the sex distribution is equal. The most common site affected is the terminal ileum. This is involved in 70% of patients, giving rise to the soubriquet of ‘terminal ileitis’ or ‘regional ileitis’. The colon may also be involved, and Crohn’s colitis is the only manifestation of disease in 20% of cases. Multiple sites are common: Crohn’s disease occurs in a discontinuous pattern within the bowel such that affected areas may be separated by quite normal bowel. These affected areas are termed skip-lesions.