Colitis

Colitis

A micrograph demonstrating cryptitis, a microscopic correlate of colitis. H&E stain.
ICD-10	K50 - K52
ICD-O:
ICD-9	558
OMIM	191390
MedlinePlus	001125
eMedicine	ped/435
DiseasesDB	31340

Colitis (or colonitis) is inflammation of the colon (or more generally the large intestine). Various types of colitis have been identified, such as ulcerative colitis and Crohn's disease.

Inflammation is a response by the body to address such challenges to homeostasis as the presence of disease, infection, or injury. In the short term, it can be helpful, but long term it can cause progressive damage.

Although there are many causes of colitis, such as colon cancer and inadequate blood supply, it is sometimes caused by infections, such as viruses, bacteria, or parasitic amoebas. Such infections often are traced to poor hygiene, thus emphasizing the importance of personal responsibility regarding one's body. Excessive use of antibiotics also can contribute to colitis by killing helpful bacteria and allowing the subsequent growth of harmful bacteria. The large intestine has many microbial species that are helpful, not only in digesting otherwise indigestible nutrients, but also in countering invading pathogens.

Overview

The colon is the biggest section of the large intestine. Three major portions of the large intestine generally are recognized in mammals: caecum (blind-ended pouch), colon (majority of the length of the intestine), and rectum (short, terminal segment) (Bowen 2000). However, the colon often is imprecisely used in the meaning of the whole large intestine altogether, and the various types of colitis likewise often includes inflammations in other sections of the large intestine.

An inflammation is a localized protective response of a body's living tissue to injury, infection, irritation, or allergy. Inflammation is characterized by the following quintet: redness (rubor), heat (calor), swelling (tumor), pain (dolor), and dysfunction of the organs involved (functio laesa).

Inflammation is part of the innate immune system, that is, the immediate "first-line" of defense to illness or pathogens. Inflammation, which is usually indicated by using the English suffix "-itis," is neither “healthy” nor "unhealthy" on its own. Inflammation helps fight disease or injury, such as by removing pathogens and debris, and walling off infection from spreading. However, it comes at the cost of suspending the body's normal immune and catabolic processes. In the short term, this is often a valid trade-off, but in the long term it is harmful to the body.

Inflammation is not a synonym for infection. Even in cases when it is caused by infection, it is incorrect to use the terms as synonyms—Infection is caused by an outside agent, while inflammation is the body's response.

Signs and symptoms

Signs and symptoms of colitis include pain, tenderness in the abdomen, fever, swelling of the colon tissue, bleeding, erythema (redness) of the surface of the colon, rectal bleeding, and ulcerations of the colon. Common tests which reveal these signs include X-rays of the colon, testing the stool for blood and pus, sigmoidoscopy, and colonoscopy. Additional tests include stool cultures and blood tests, including blood chemistry tests. A high erythrocyte sedimentation rate (ESR) is one typical finding in acute exacerbations of colitis.

Types

Types of colitis include ulcerative colitis, Crohn's colitis, diversion colitis, ischemic colitis, infectious colitis, fulminant colitis, and chemical colitis.

A well-known subtype of infectious colitis is pseudomembranous colitis, which results from infection by a toxigenic strain of Clostridium difficile. Parasitic infections can also cause colitis.

Any colitis with a rapid downhill clinical course is known as fulminant colitis. In addition to the diarrhea, fever, and anemia seen in colitis, the patient has severe abdominal pain and presents a clinical picture similar to that of septicemia, where shock is present. Approximately half of these patients require surgery.

Irritable bowel syndrome, a separate disease, has been called spastic colitis or spastic colon. This name causes confusion, since colitis is not a feature of irritable bowel syndrome.

Ulcerative colitis

Ulcerative colitis (Colitis ulcerosa, UC) is a type of colitis that includes characteristic ulcers, or open sores, in the colon. It is also classified as a form of inflammatory bowel disease (IBD), a group of inflammatory conditions of the large intestine and, in some cases, the small intestine. The main symptom of active disease is usually diarrhea mixed with blood, of gradual onset. Ulcerative colitis is, however, a systemic disease that affects many parts of the body outside the intestine. Ulcerative colitis is similar to Crohn's disease, another form of IBD. Ulcerative colitis is an intermittent disease, with periods of exacerbated symptoms, and periods that are relatively symptom-free. Although the symptoms of ulcerative colitis can sometimes diminish on their own, the disease usually requires treatment to go into remission. Ulcerative colitis is a rare disease, with an incidence of about one person per 10,000 in North America.

Crohn's disease

Crohn's disease (also known as regional enteritis) is a chronic, episodic, inflammatory condition of the gastrointestinal tract characterized by transmural inflammation (affecting the entire wall of the involved bowel) and skip lesions (areas of inflammation with areas of normal lining in between). Crohn's disease is a type of inflammatory bowel disease (IBD) and can affect any part of the gastrointestinal tract from mouth to anus; as a result, the symptoms of Crohn's disease vary between affected individuals. The main gastrointestinal symptoms are abdominal pain, diarrhea (which may be bloody), and weight loss. Crohn's disease can also cause complications outside of the gastrointestinal tract such as skin rashes, arthritis, and inflammation of the eye (Hanauer 1996).

Diversion colitis

Diversion colitis is an inflammation of the colon which can occur as a complication of ileostomy or colostomy, often occurring within the year following the surgery. It can also occur in a neovagina created by colovaginoplasty, sometimes several years after the original procedure. In many milder cases after ileostomy or colostomy, diversion colitis is left untreated and disappears naturally. If treatment is required, possible treatments include short-chain fatty acid irrigation, steroid enemas, and mesalazine.

Ischemic colitis

Ischemic colitis is a medical condition in which inflammation and injury of the large intestine result from inadequate blood supply. Although uncommon in the general population, ischemic colitis occurs with greater frequency in the elderly, and is the most common form of bowel ischemia (Higgins et al. 2004; Brandt and Boley 2000).

Chemical colitis

Chemical colitis is a type of colitis caused by the introduction of harsh chemicals to the colon by an enema or other procedure. Chemical colitis can resemble ulcerative colitis, infectious colitis, and pseudomembranous colitis endoscopically. Prior to 1950, hydrogen peroxide enemas were commonly used for certain conditions. This practice will often result in chemical colitis. Soap enemas may also cause chemical colitis (Harish et al. 2006). Harsh chemicals, such as compounds used to clean colonoscopes, are sometimes accidentally introduced into the colon during colonoscopy or other procedures. This can also lead to chemical colitis.

Treatment

Treatment of colitis may include the administration of antibiotics and general anti-inflammatory medications, such as Mesalamine or its derivatives, steroids, or one of a number of other drugs that ameliorate inflammation. Surgery is sometimes needed, especially in cases of fulminant colitis. Surgery usually entails removing the colon and bowel and creating a "pouch" with portions of the small intestine.

Changes in diet can be effective at treating the symptoms of colitis and easing the side effects. These can include reducing the intake of carbohydrates, lactose products, soft drinks, and caffeine.

References

ISBN links support NWE through referral fees

• Bowen, R. The large intestine: Introduction and index Colorado State, 2006. Retrieved March 28, 2017.
• Bowen, R. Gross and microscopic anatomy of the large intestine Colorado State, 2000. Retrieved March 28, 2017.
• Brandt, L. J, and S. J. Boley. “AGA technical review on intestinal ischemia.” Gastroenterology. 118(5): 954-968, 2000. PMID 10784596 Retrieved March 28, 2017.
• Hanauer, S. B. Inflammatory bowel disease New England Journal of Medicine. 334(13): 841-848, 1996. PMID 8596552 Retrieved March 28, 2017.
• Harish, K., J. Tony, R. Sunilkumar, and T. Varghese. “Severe colitis induced by soap enemas.” Indian J. Gastroent. 25(2): 99-100, 2006.
• Higgins, P., K. Davis, and L. Laine. “Systematic review: The epidemiology of ischaemic colitis.” Aliment Pharmacol Ther. 19(7): 729-738, 2004. PMID 15043513 Retrieved March 28, 2017.

External links

All links retrieved March 28, 2017.

• Crohn's & Colitis Foundation of Canada
• Crohn's & Colitis Foundation of America