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Colitis

Ulcerative colitis is an inflammatory disease of the bowel, that usually affects the distal end of the large intestine and rectum. It has no known cause, although there is a genetic component to susceptibility.

Ulcerative colitis is similar to Crohn's disease, but there are characteristic differences. Ulcerative colitis affects only the colon and cannot "migrate" to the small intestine, while Chron's disease can affect the entire digestive tract. Complete colon removal can thus be considered a "cure" for ulcerative colitis. Ulcerative colitis is usually confined to the mucosal and submucosal lining of the colon, and affects whole areas of intestine. Crohn's disease, on the other hand tends to be patchy, and affect more layers of intestine, being transmural in nature. Due to the nature of the inflammation, Ulcerative colitis rarely requires resection surgery in contrast to Chron's disease where such surgery is often needed due to dangerous bowel obstructions and other complications. However, the risk of colorectal cancer development in ulcerative colitis patients is significantly greater (up to 5 times) than general population after 10 years following the diagnosis.

Signs and Symptoms of Ulcerative Colitis

• Chronic (> 6 months) of diarrhea (sometimes bloody).
• No infective cause of diarrhea found.
• Inflammatory changes are most often confined to the left side and distal parts of the large intestine, however, any part of the colon can be affected. Inflammatory changes can expand over time and affect larger areas of the colon.
• Disease variable in severity from patient to patient and time to time. This makes long-term prognosis very difficult, since a specific patient may remain in clinical remission for years between exacerbations.
• Significant risk of carcinoma after 10 years, due to degenerative processes in the mucous lining of the colon (primarily pseudopolyposis), which may in some cases require frequent surveillance biopsies or even prophylactic bowel removal.
• Patients may have other auto-immune features and extra-bowel complications including but not limited to iritis, uveitis, episcleritis, migratory polyarthritis, sacroiliitis, erythema nodosum, fingertip clubbing, and ankylosing spondylitis.
• Fistula formation is rare but does occur. However, unlike Crohn's disease, the probability of recurrence is low.
• Often found in former smokers. Stopping smoking can cause a reduction in the protective mucus lining the colon. When this protective mucus is reduced, the bacteria in the colon can attack the colon lining causing the immune system to become active and fight the bacteria. For unknown reasons, this causes damage to the lining (ulcers) of the colon walls in one or more places. Resumption of nicotine either through patches or smoking can extend remission time although the benefits versus the other health risks of smoking are questionable.

The cause of ulcerative colitis is unknown, although infective agents have been suspected, and there is a genetic component to susceptibility. Immune system over-activity has also been suspected as a cause. There is much research currently being conducted in this area, and some new theories and medications show promising results. While a definitive cause of Ulcerative colitis may never be discovered (since it is highly possible that it is a result of a combination of enviromental, genetical, bacterial and other factors), an effective treatment or even a cure may not be very far away.

Diagnosis of Colitis

A long-standing history of bloody diarrhea, with no sign of infection, is consistent with ulcerative colitis. A diagnosis is usually achieved through colonoscopy with biopsy of pathological lesions. Ulcerative colitis most often affects the rectum and the distal left side of the colon, but can occur anywhere in the large intestine. Pan-colitis is a full-blown inflamation of the entire colon, and is especially hard to treat.

People with ulcerative colitis may initially have bloody diarrhea (the severity of which is variable from time to time). Because of destruction of the nerves in the bowel, movement may be impaired, and the intestine may dilate. This may, in some cases, result in an extreme diarrheal disease - toxic megacolon, however the probability of occurance is very low, and is further reduced by regular routine surveillance by colonoscopy. Eventually the inflamed mucosa may develop a risk of malignancy, requiring biopsy every few months. Sometimes the risk of malignancy is such that bowel resection is offered. Many secondary complications are due to the nature of some medication prescribed for treatment of the symptoms, notably corticosteroids and immunosupresive agents, and long-term use of these drugs should be avoided if at all possible.

However, in most ulcerative colitis cases prognosis is relatively good, as remission can often be maintained through relatively harmless anti-inflammatory medication and most patients may never require any kind of surgery for their condition. While quality of life can often be impaired by unpleasant symptoms such as pain, vomiting and chronic diarrhea, the disease is very rarely fatal on its own, and most patients enjoy normal symptom-free lives while in remission.

Treatment of Colitis

• Anti-diarrheal drugs (such as loperamide) should be avoided unless under specific doctors orders, as they can worsen the disease.
• Anti-inflammatory drugs (such as sulfasalazine or mesalamine) can be used, and in severe cases steroids may be given.
• Immunosuppressive agents such as azathioprine, 6-mercaptopurine (6-MP), and more recently, cyclosporine have also been used as effective preventive medications.

Surgery is rarely recommended, except in cases where drug treatment has proven completely ineffective. Since ulcerative colitis affects only the colon, a complete large intestine removal can be considered a cure. However, this leaves the patient with a permanent ileostomy, which can cause further problems in itself, not to mention the adverse psychological effect. A more aesthetically and functionaly pleasing resolution may be a j-pouch surgery, where a part of the terminal ileum is used to create a "pouch" which is then connected to the anus. This preserves the appearance of normal bowel function, although bowel movements are somewhat more frequent.

There is no proven connection between dietary habits and the onset of the disease. Although opinions are somewhat divided on this issue it is safe to say that no particular diet can influence length of remission or cause inflammation if none is present. The usual recommendation for patients is to simply avoid foods that have caused them discomfort in the past, and try to eat as healthy as possible. This does not apply to acute onsets of the disease when a patient should try and maintain a low-fat and generaly bland diet to facilitate faster and easier healing.

Pseudomembranous colitis

Pseudomembranous colitis is a infection of the colon caused by the bacterium Clostridium difficile. The illness is characterized by diarrhea, fever, and abdominal pain. It can be severe and even fatal.

In most cases the patient had recently been on antibiotics. Antibiotics disturb the normal bowel bacterial flora that generally keeps the bacteria Clostridium difficile under control. Clindamycin is the antibiotic associated with this disorder classically, but any antibiotic can cause the condition. Additional groups at increased risk are diabetics and the elderly. Half of cases are not associated with risk factors.

The disease is ususally treated with metronidazole. Oral vancomycin is an alternative drug. Occasionally metronidazole has been associated with the development of pseudomembranous colitis. In these cases metronidazole is still effective treatment, since the cause of the colitis is not the antibiotic, but rather the change in bacterial flora from a previous round of antibiotics. If antibiotics do not control the infection the patient may require a colectomy (removal of the colon) for treatment of the colitis.

Posted by Staff at May 17, 2005 2:35 AM

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