Overview of Ulcerative Colitis
Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) that affects all or part of the large intestine or large bowel, resulting in inflammation and ulceration (sores) of the inner lining (mucosa) of the organ. Ulcerative colitis can significantly affect the quality of life, and in some cases, can lead to life-threatening complications.
The large intestine is located between the small intestine and the anus. It consists of the colon and the rectum. The colon consists of the cecum (connects to the small intestine at the cecal valve), the ascending colon (vertical segment located on the right side of the abdomen), the transverse colon (extends across the abdomen), the descending colon (leads vertically down the left side of the abdomen), and the sigmoid colon (extends to the rectum). The rectum is the last segment of the large intestine. Waste material (i.e., stool or fecal matter) is stored in the rectum until it is eliminated from the body through the anus.
There are several types of ulcerative colitis, depending on location in the large intestine. Each type causes slightly different symptoms. Types of ulcerative colitis include the following:
- Limited or distal colitis (only the left side of the colon is affected)
- Pan-ulcerative (total) colitis (affects the entire colon)
- Proctosigmoiditis (affects the rectum and sigmoid [lower] colon)
- Ulcerative proctitis (only affects the rectum)
Symptoms of ulcerative colitis are similar to symptoms of other inflammatory bowel diseases, such as Crohn's disease. Ulcerative colitis is not related to irritable bowel syndrome (IBS).
Incidence and Prevalence of Ulcerative Colitis
It is estimated that as many as 1 million people in the United States have inflammatory bowel disease (IBD)and that about 620,000 are affected by ulcerative colitis.
Ulcerative colitis can occur at any age; however, initial symptoms usually appear between the ages of 30 and 40. Caucasians are at higher risk than people of other races. People of Jewish or European descent are 4-5 times more likely to develop the disease than the general population.
UC affects men and women equally, and appears to run in families. Approximately 20% of patients who have the condition also have a primary family member (i.e., parent, child, sibling) diagnosed with either ulcerative colitis or Crohn's disease.