IBD

Inflammatory bowel disease (IBD) is a chronic, relapsing inflammatory condition of the gastrointestinal tract. It mainly refers to Crohn's disease and ulcerative colitis. Most often begins in adolescence or early adulthood; incidence has risen in many regions.

Crohn's disease can affect any part of the GI tract from mouth to anus, often with skipped areas and transmural inflammation, leading to strictures or fistulas. Ulcerative colitis is limited to the colon and rectum, with continuous mucosal inflammation beginning in the rectum.

Symptoms include abdominal pain, chronic diarrhea, blood in stool, weight loss, and fatigue. Extraintestinal manifestations may occur (joints, eyes, skin). Diagnosis uses history, examination, lab tests (anemia, C-reactive protein), stool studies to exclude infection, endoscopy with biopsies, and imaging.

Treatment aims to induce and maintain remission and prevent complications. Approaches include aminosalicylates, corticosteroids, immunomodulators (azathioprine, 6-mercaptopurine [6-MP]), and biologics (anti-TNF agents, vedolizumab, ustekinumab). In UC, tofacitinib is an option in some guidelines. Nutrition, vaccination, and lifestyle support are important. Surgery may be needed for complications; colectomy can cure some UC cases; Crohn's may require resection.

Long-term management involves monitoring disease activity and colorectal cancer risk, especially with extensive colitis. The exact cause is unknown, but IBD reflects interactions among genetic susceptibility, immune dysregulation, and environmental factors. Smoking influences disease course (Crohn's worsens; UC may improve).