Get answers to your Ulcerative Colitis questions.
Inflammatory bowel disease - ulcerative colitis; Colitis - ulcerative
Researchers do not know the exact causes of inflammatory bowel disease. IBD appears to be due to an interaction of many complex factors including genetics, impaired immune system response, and environmental triggers. The result is an abnormal immune system reaction, which in turn causes an inflammatory response in the body‚ ' s intestinal regions.
The Immune System's Infection Fighters. The primary infection-fighting units are two types of white blood cells: lymphocytes and leukocytes.
Lymphocytes include two subtypes known as T cells and B cells. Both types of cells are designed to recognize foreign invaders (antigens) and to launch an offensive or defensive action against them:
T cells are further categorized as killer T cells or helper T cells.
Helper T Cells and Inflammatory Bowel Disease. The actions of the helper T cells (TH cells) are of special interest in inflammatory bowel disease:
Helper T cells are further categorized as TH1 and TH2. An imbalance in these two types appears to occur in inflammatory bowel disease (IBD), although each disorder has a different balance.
Although the exact causes of inflammatory bowel disease are not yet known, genetic factors certainly play some role. Between 10 - 20% of people with ulcerative colitis have family members with the disease. Several identified genes and chromosome locations play a role in the development of ulcerative colitis, Crohn's disease, or both. Genetic factors appear to be more important in Crohn's disease, although there is evidence that both conditions have some genetic defects in common.
In 2006, scientists identified variations in the interleukin-23 receptor (IL23R) as an important genetic link to both Crohn‚ ' s disease and ulcerative colitis. Interleukin 23 is a cytokine that plays an important part in the inflammatory response and inflammatory diseases. Interestingly, scientists found that certain variations in the IL23 receptor gene can either increase or decrease the risk for inflammatory bowel disease.
Some studies have reported that children with IBD may have had more and earlier childhood infections. The measles virus has been of particular interest. However, according to the U.S. Centers for Disease Control and Prevention, and many studies, the measles virus does not cause Crohn‚ ' s or IBD. In addition, studies conclusively report that the measles, mumps, and rubella (MMR) vaccine does not cause Crohn‚ ' s disease, ulcerative colitis, or autism.
Inflammatory bowel disease is much more prevalent in industrialized nations and in higher-income groups. However, there is no strong evidence that diet or particular types of food cause Crohn‚ ' s disease or ulcerative colitis.
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