Which disease is described as the autoimmune form of inflammatory bowel disease affecting both the small and large intestine?

• A. Crohn's Disease
• B. Ulcerative Colitis
• C. Irritable Bowel Syndrome
• D. Celiac Disease

Answer: (A)

Crohn's disease is the autoimmune inflammatory bowel disease that can involve both the small and large intestine. It reflects an immune-mediated attack on the gut, and unlike some other bowel diseases, it can affect any part of the gastrointestinal tract—from mouth to anus—though it most often involves the terminal ileum and the colon. The inflammation is transmural, meaning it goes through the full thickness of the bowel wall, which is why Crohn's can cause complications like fistulas and strictures. In contrast, ulcerative colitis is limited to the colon and affects only the mucosal layer with continuous involvement starting at the rectum, irritable bowel syndrome is not inflammatory or autoimmune, and celiac disease is an autoimmune reaction to gluten that primarily damages the small intestine but is not classified as an inflammatory bowel disease of the colon.