Understanding Inflammatory Bowel Disease (IBD)
Inflammatory Bowel Disease (IBD) is a term used to describe chronic inflammation of the gastrointestinal tract. While Crohn’s disease and ulcerative colitis are the two most common types of IBD [1], there are several other less common forms:
- Microscopic Colitis
- Indeterminate Colitis
- Behçet's Disease
- Primary Sclerosing Cholangitis (PSC) with IBD
These conditions are characterised by periods of active disease (flares) and periods of remission (when symptoms are reduced or absent).
What is Crohn’s Disease?
Crohn’s disease is a type of IBD that can affect any part of the gastrointestinal tract from the mouth to the anus, but most commonly affects the end of the small intestine (ileum) and the beginning of the colon. In Crohn’s disease:
- Inflammation may extend through all layers of the bowel wall [2]
- Affected areas may be patchy, with healthy sections in between (known as "skip lesions")
- Common symptoms include abdominal pain, diarrhoea, fatigue, weight loss, and malnutrition
- Complications can include strictures (narrowing of the intestine), fistulas (abnormal connections between organs), and abscesses [3]
What is Ulcerative Colitis?
Ulcerative colitis is a type of IBD that affects only the colon (large intestine) and rectum. In ulcerative colitis:
- Inflammation is typically limited to the innermost lining of the colon [4]
- The inflammation is continuous, starting from the rectum and potentially extending throughout the colon
- Common symptoms include bloody diarrhoea, abdominal cramping, urgency to defecate, and fatigue
- Complications can include severe bleeding, toxic megacolon, and increased risk of colorectal cancer [5]
How Are They Related?
Both Crohn’s disease and ulcerative colitis:
- Are chronic inflammatory conditions of the digestive tract
- Have similar symptoms and can significantly impact quality of life
- Are believed to result from an abnormal immune response to environmental triggers in genetically susceptible individuals [6]
- Have no known cure, but treatments can help manage symptoms and achieve remission
- Often appear in young adults between the ages of 15 and 35, though they can develop at any age [7]
How Do They Differ?
Despite their similarities, there are important differences between Crohn’s disease and ulcerative colitis:
| Feature | Crohn's Disease | Ulcerative Colitis |
|---|---|---|
| Location | Can affect any part of the GI tract | Limited to the colon and rectum |
| Pattern | Patchy inflammation with skip lesions | Continuous inflammation |
| Depth | Can affect all layers of the bowel wall | Typically affects only the innermost lining |
| Complications | Strictures, fistulas, abscesses | Severe bleeding, toxic megacolon |
| Surgical outcomes | Surgery may induce remission, but not cure the disease | Total colectomy can "cure" ulcerative colitis |
Diagnosis
Diagnosis of IBD typically requires an endoscopic procedure, particularly to determine which IBD. The diagnosis process may involve a combination of:
- Medical history and physical examination
- Blood tests to check for anaemia, inflammation markers, and antibodies
- Stool tests to rule out infections and check for inflammation
- Imaging studies such as computed tomography (CT) scans, magnetic resonance imaging (MRI), and intestinal ultrasound (IUS) [8]
- Endoscopic procedures (colonoscopy and/or upper endoscopy)
Treatment
Treatment approaches for both conditions may include:
- Anti-inflammatory medications (e.g. aminosalicylates, corticosteroids)
- Immunosuppressants
- Biologic therapies (e.g. TNF blockers, Integrin blockers, Interleukin blockers, JAK blockers)
- Antibiotics
- Surgery [9]
Living with IBD
While IBD is a chronic condition, many people with Crohn’s disease or ulcerative colitis lead full, active lives with proper management. Working closely with healthcare providers, maintaining a healthy lifestyle, and connecting with support groups can help individuals effectively manage their condition. [10]
References
- Kaplan GG. The global burden of IBD: from 2015 to 2025. Nat Rev Gastroenterol Hepatol. 2015;12(12):720-727. doi:10.1038/nrgastro.2015.150
- Baumgart DC, Sandborn WJ. Crohn's disease. Lancet. 2012;380(9853):1590-1605. doi:10.1016/S0140-6736(12)60026-9
- Torres J, Mehandru S, Colombel JF, Peyrin-Biroulet L. Crohn's disease. Lancet. 2017;389(10080):1741-1755. doi:10.1016/S0140-6736(16)31711-1
- Ungaro R, Mehandru S, Allen PB, Peyrin-Biroulet L, Colombel JF. Ulcerative colitis. Lancet. 2017;389(10080):1756-1770. doi:10.1016/S0140-6736(16)32126-2
- Danese S, Fiocchi C. Ulcerative colitis. N Engl J Med. 2011;365(18):1713-1725. doi:10.1056/NEJMra1102942
- Khor B, Gardet A, Xavier RJ. Genetics and pathogenesis of inflammatory bowel disease. Nature. 2011;474(7351):307-317. doi:10.1038/nature10209
- Molodecky NA, Soon IS, Rabi DM, et al. Increasing incidence and prevalence of the inflammatory bowel diseases with time, based on systematic review. Gastroenterology. 2012;142(1):46-54.e42. doi:10.1053/j.gastro.2011.10.001
- Maaser C, Sturm A, Vavricka SR, et al. ECCO-ESGAR Guideline for Diagnostic Assessment in IBD Part 1: Initial diagnosis, monitoring of known IBD, detection of complications. J Crohns Colitis. 2019;13(2):144-164. doi:10.1093/ecco-jcc/jjy113
- Torres J, Bonovas S, Doherty G, et al. ECCO Guidelines on Therapeutics in Crohn's Disease: Medical Treatment. J Crohns Colitis. 2020;14(1):4-22. doi:10.1093/ecco-jcc/jjz180
- Kemp K, Dibley L, Chauhan U, et al. Second N-ECCO Consensus Statements on the European Nursing Roles in Caring for Patients with Crohn's Disease or Ulcerative Colitis. J Crohns Colitis. 2018;12(7):760-776. doi:10.1093/ecco-jcc/jjy020
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