Ulcerative colitis is a disease characterized by a chronic inflammatory reaction involving the mucosa and submucosa of the large intestine. It occurs in both sexes and in all age-groups. It is basically a disease of young adults, although close to 15% of the cases begin in children younger than 16 years. The peak onset in children is between ages 10 and 19. This disorder and Crohn's disease are together referred to as inflammatory bowel disease.

The cause of ulcerative colitis is unknown, although infectious, nutritional, immunologic, and psychogenic etiologies have been proposed but not substantiated. At present the feeling is that Ulcerative colitis is an organic disease caused by combination of physical and emotional factors. Psychologic influences, such as stress, significantly affect the exacerbation and chronicity of the illness. Several genetic and environmental factors influence the incidence of ulcerative colitis
• There is a familial tendency in about 5% to 15% of the cases,
• Individuals from higher socio-economic evels and more whites than nonwhites are affected
• The incidence is four times greater in Jewish populations than in the general population, and
• There is a higher occurrence of allergic disease in relatives of these patients

Pathophysiology
The mucous membranes of the bowel become hyperemic and edematous with the formation of patchy granulations over the intestinal surface ulcerations. In longstanding disease, the bowel becomes narrowed, smooth, and inflexible with thin or absent mucosa heavily infiltrated by scar tissue. The greatly reduced absorptive surface results in loose, watery and sometimes bloody stools.

Clinical manifestations
The most common feature of ulcerative colitis is persistent or recurring diarrhea. In acute, fulminating disease there is bloody diarrhea preceded by cramping abdominal pain and followed by abdominal distention. Diarrhea may be very severe with marked urgency and frequency (20 to 30 stools daily). It is usually associated with fever, weight loss, anorexia, and sometimes nausea and vomiting. Pallor and anemia may result from bleeding and reduced dietary intake, and the numerous watery bowel movements often cause depletion of water and electrolytes.

The clinical course varies markedly in terms of severity, response to therapy, and prognosis. In general the disease follows one of two patterns: acute remitting type or chronic continuous course. Children afflicted with either type have usually been healthy before the onset of the disease. The acute remitting type is more common and follows a pattern of remissions and exacerbations. During the period of remission, the child is usually well, with few or no symptoms of disease. However, periods of exacerbation are severe and acute, although they usually respond well to medical treatment, The disease may terminate in a permanent remission or ultimately follow the course of chronic colitis.

In chronic continuos colitis, there are no definitive periods of severe disease with intermittent good health. Intestinal symptoms tend to be less severe, but chronic malnutrition and anemia are common, These children often respond poorly to medical therapy and are more likely to suffer from complications, especially carcinoma of the colon.

Therapeutic management
Medical treatment is based on a combination of therapies:
1. dietary managements to allow the colon a rest and improve the child's nutritional status,
2. medication to reduce the abdominal pain and rectal spasm
3. steroids to reduce bowel inflammation, and
4. antibacterial agents (sulfasalazine) to prevent infection.

The child is usually hospitalized both to ensure proper medical management and to reduce the familial environmental factors that may be contributing to the disease. Other medical therapies that may be warranted include intravenous fluids, to correct dehydration and associated electrolyte imbalances, and parenteral alimentation when malnutrition is severe and the colitis is further aggravated by oral diet. Emergency surgical intervention is required for complications such as perforation, massive hemorrhage, or toxic megacolon (fulminating distention of the colon with progressive inflammation).

In some instances a poor response to medical treatment necessitates elective surgery either to allow the bowel a period of rest, in which a temporary colostomy is performed, or to arrest the disease process by removing the entire section of ulcerated bowel, in which case a total colectomy or ileostomy is usually required. In which case a total colectomy or ileostomy is usually required. In some centers a prophylactic colectomy is considered in those children with chronic colitis of 10 years of more duration to eliminate the high risk of colonic cancer.

A possible alternative to a permanent colostomy or ileostomy is the continent (Koch) ileostomy. In this procedure an intraabdominal puch or reservoir is constructed form the terminal ileum. The feces are stored in the puch until the patient drains it with a catheter. A surgically implanted valve prevents leakage of feces. The stoma is less than a inch in diameter, is almost level with the skin and requires no appliance. These are obvious advantages, especially to an adolescent who is concerned with body image and self- identity.

Psychotherapy or family counseling may also prove helpful in reducing stresses that existed before the disease and those that have resulted from the colitis. A particularly difficult stress for these children to cope with is the consequence growth retardation and delayed sexual maturation from chronic colitis. Supportive therapy may also be of benefit to those children facing the adjustment of a permanent ileostomy.

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