[Circumstances of the diagnosis and clinical course of inflammatory bowel disease]

The diagnosis of inflammatory bowel disease is sometimes difficult. The cardinal symptom of ulcerative colitis is bloody diarrhoea. The clinical characteristics of Crohn's disease are more heterogeneous, but typically include abdominal pain in the right lower quadrant, diarrhoea, weight loss and/or perianal disease. Extra intestinal (joint, cutaneaous and eye) manifestations can precede digestive symptoms and lead to the diagnosis of inflammatory bowel disease. The clinical course of these two diseases is unpredictable. The risk of colorectal cancer is significantly increased 8 years after diagnosis of pancolitis. Thus, regular surveillance by colonoscopy with random biopsies is recommended.