Inflammatory bowel disease

In medicine, inflammatory bowel disease (IBD) is a group of inflammatory conditions of the large intestine and, in some cases, the small intestine. It should not be confused with IBS, irritable bowel syndrome, which is an inconvenient yet more innocent disease.

Forms

The main forms of IBD are Crohn's disease and ulcerative colitis (UC).

Accounting for far fewer cases are other forms of IBD:

The main difference between Crohn's disease and UC is the location and nature of the inflammatory changes in the gut. Crohn's can affect any part of the gastrointestinal tract, from mouth to anus (skip lesions), although a majority of the cases start in the terminal ileum. Ulcerative colitis, in contrast, is restricted to the colon, and spares the anus.

Microscopically, ulcerative colitis is restricted to the mucosa (epithelial lining of the gut), while Crohn's disease affects the whole bowel wall.

Finally, Crohn's disease and UC present with extra-intestinal manifestations (such as liver problems, arthritis, skin manifestations and eye problems) in different proportions.

In rare cases, a patient has been diagnosed with both Crohn's disease and Ulcerative Colitis, though whether it is a combination or simply unidentifiable as one or another is uncertain.

Diagnosis

Although very different diseases, both may present with any of the following symptoms: abdominal pain, vomiting, diarrhea, hematochezia, weight loss and various associated complaints or diseases (arthritis, pyoderma gangrenosum, primary sclerosing cholangitis). Diagnosis is generally by colonoscopy with biopsy of pathological lesions.

Treatment

All forms of IBD may require immunosuppression to control the symptoms. This consists of mesalazine, steroids, and later of steroid-sparing agents (such as azathioprine, methotrexate or 6-mercaptopurine) or biologicals. Severe cases may require surgery, such as bowel resection, strictureplasty or a temporary or permanent colostomy or ileostomy.

Prognosis

While IBD can limit quality of life due to pain, vomiting, diarrhea, and other socially unacceptable symptoms, it is rarely fatal on its own. Fatalities due to complications such as toxic megacolon, bowel perforation and surgical complications are also rare.

While patients of IBD do have an increased risk of colorectal cancer this is usually caught much earlier than the general population in routine surveillance of the colon by colonoscopy, and therefore patients are much more likely to survive.

Recent findings

A recent hypothesis posits that some IBD cases are caused by an overactive immune system attacking various tissues of the digestive tract because of the lack of traditional targets such as parasites and worms. The number of people being diagnosed with IBD has increased as the number of infections by parasites, such as roundworm and human whipworms, has fallen, and the condition is still rare in countries where parasitic infections are common. This is similar to the hygiene hypothesis applied to allergies.

Initial reports (Summers et al 2003) suggest that "helminthic therapy" may not only prevent but even cure (or control) IBD: a drink with roughly 2500 ova of the Trichuris suis helminth taken twice monthly decreased symptoms markedly in many patients. It is even speculated that an effective "immunization" procedure could be developed - by ingesting the coctail at an early age.

Prebiotics and probiotics are showing increasing promise as treatments for IBD (Furrie, 2005) and in some studies have proven to be as effective as prescription drugs (Kruis, 2004).

References

Furrie, E. Biotic Therapy Cuts Inflammation in Ulcerative Colitis. Gut 2005;54:242-249.
Kruis, W., P Fric, J Pokrotnieks, M Lukás, B Fixa, M Kascák, M A Kamm, J Weismueller, C Beglinger, M Stolte, C Wolff, and J Schulze. Maintaining remission of ulcerative colitis with the probiotic Escherichia coli Nissle 1917 is as effective as with standard mesalazine. Gut 2004; 53: 1617-1623.
Summers RW, Elliott DE, Qadir K, Urban JF Jr, Thompson R, Weinstock JV. Trichuris suis seems to be safe and possibly effective in the treatment of inflammatory bowel disease. Am J Gastroenterol 2003;98:2034-41. PMID 14499784.

External links

CrohnsZone.org - Self-help organisation for sufferers of colitis and Crohn's disease- UK
Crohn's and Colitis Foundation of America
Help for Irritable Bowel Syndrome - Patient education, treatments, and community for IBD patients with concommitant IBS
National Association for Colitis & Crohn's disease (NACC)- UK

Gastroenterology | Autoimmune diseases