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Ulcerative Colitis

Ulcerative colitis is a disease of the colon in which the mucosa is affected by acute inflammation with the predominant cell type being the polymorphonuclear leukocyte. The inflammation may affect only the rectum, or spread proximally in a contiguous fashion until the entire colon is involved. The small bowel is not involved in the process except in rare instances where a short segment of terminal ileum is involved with inflammation and is given the term "backwash ileitis". The disease occurs in both men and women with nearly equal incidence. It tends to be a young persons disease, but can occur in the older population as well, where it is frequently misdiagnosed as ulcerative colitis.

Etiology

The etiology of ulcerative colitis is not known. The various theories regarding its pathogenesis have varied from the psychiatric, to the food induced, allergic, immunologic, and infectious. To date, the psychiatric, food induced and allergic causes have largely fallen by the wayside. The immunologic and infectious causes have many supporters but as yet no one has the definite proof if either is the one. To some extent, the fact that antibiotics have a role in treatment of the disease represents the most powerful support for the infectious etiology theory. The familial incidence of both Crohn's and ulcerative colitis has been noted but the precise pattern of inheritance and the molecular basis.

Clinical manifestations

The patient may have diarrhea and bleeding as the major manifestation. If the rectum is the only segment involved, there may actually be constipation. The inflammation of the rectum may give the sensation that the patient has to defecate due to the stimulation of the normal rectal sensory mechanisms and is termed tenesmus. The disease may be mild, moderate, or severe.

Systemic manifestations

Multiple systemic manifestations are possible. The skin may be involved by pyoderma gangrenosum, a noninfectious ulceration, which may affect any part of the skin. The ulcer may be small to start but can get large and involve much of the skin surface. It is thought to represent a vasculitis. Aphthous ulcers in the mouth are typical in IBD, especially in Crohn's disease. Erythema nodosum is another skin process, which can occur in IBD. Painful red nodules on the extensor surfaces.

Medical Therapy

The treatment of patients with IBD requires management of general medical issues such as fluid and electrolyte replacement, and attention to nutrition.

5-Acetylsalicylic Acid (5-ASA)

The first drug used in the treatment of ulcerative colitis was sulfasalazine. This drug was used to treat rheumatoid arthritis in the 1940% and was serendipitously noted to improve colitis in those patients who coincidentally had the two conditions simultaneously. The drug consists of a salicylate moiety attached to a sulfa molecule.

Corticosteroids

Corticosteroids were recognized soon after their introduction in the 1950s as being powerful anti-inflammatory agents and proved very useful in the treatment of ulcerative colitis. The steroids are very effective in acute colitis, but because of their many side effects, are not good for the long term maintenance of a remission. Doses as high as 80 mg of methylprednisone.

Immunomodulator Therapy: Cyclosporine and 6-Mercaptopurine

The interest in non corticosteroid treatment options for IBD has resulted in the discovery of cyclosporine for the treatment of IBD. The drug interferes with interleukin formation and is very effective in the treatment of severe ulcerative colitis. In many studies, it clearly can reverse the course of severe or even fulminant ulcerative colitis, which has not responded to conventional corticosteroid treatment. In most studies, it has been effective in inducing a remission in 50-80% of patients. It is not clear however if the drug changes the natural history of the disease.

6-Mercaptopurine is a second drug in this category. There is extensive experience with this drug whose main use is in the treatment of patients with Crohn's disease which is unremitting.

Biological agents

Recently, clinical trials have been undertaken with biological agent including Tumor Necrosis Factor inhibitor and Interleukin 11 inhibitors. The data on these newer agents are intriguing and in the next couple of years should be available for our interpretation.

Other agents and approaches

Total parenteral nutrition is useful in the overall management of sick patients but probably has no primary role in the long term treatment of patients with IBD. TPN has proved useful in closing fistulas in patients with Crohn's disease, but generally these tend to recur once the patients are eating once again. The role of TPN is therefore to enhance the general well being.

Cigarette smoking is unequivocally associated with a beneficial effect in patients with ulcerative colitis but not in patients.

Pregnancy in IBD

The course of pregnancy in patients with IBD tends to reflect the activity of the disease. Thus, in patients with uncomplicated disease pregnancy tends not to be any more complicated.

Surgical treatment

The treatment of ulcerative colitis by removal of the colon and rectum is curative of the disease and the treatment of choice in patients with unremitting disease or with toxic dilation of the colon. The latter patients have a high mortality if not aggressively treated with early colectomy. The modern treatment for most patients with ulcerative colitis involves the removal.

Carcinoma of the colon

Carcinoma of the colon is a complication of longstanding ulcerative colitis and Crohn's disease. It occurs more frequently in ulcerative colitis than in Crohn's and becomes an important problem.