Type of inflammatory bowel disease that may affect any part of the GI tract from mouth to anus.

• A. Crohn's disease
• B. Ulcerative colitis
• C. Celiac disease
• D. Irritable bowel syndrome

Answer: (A)

Crohn's disease is the inflammatory bowel disease that can involve any part of the gastrointestinal tract from mouth to anus. The hallmark is transmural inflammation, which means the inflammation can affect all layers of the bowel wall and can occur in any segment—from the mouth to the anus—often in a patchy, skip-lesion pattern. This contrasts with ulcerative colitis, which is limited to the colon and rectum and presents with continuous mucosal inflammation starting at the rectum. Celiac disease is an autoimmune reaction to gluten that damages the small intestine and is not considered an inflammatory bowel disease in the same sense. Irritable bowel syndrome is a functional disorder with no identifiable inflammatory changes. So the description fits Crohn's disease.