Pathophysiology of inflammatory bowel disease: an overview.

Inflammatory bowel disease, Crohn's disease, and ulcerative colitis are considered idiopathic diseases affecting the gastrointestinal tract. These two diseases are often considered together because of multiple similarities, including gastrointestinal inflammation, waxing and waning severity and symptoms, and unknown etiology. However, they have separate symptoms and microscopic characteristics as well as patterns within the gastrointestinal tract.