Understanding Ulcerative Colitis (UC)
Updated July 23, 2013
Ulcerative colitis is the result of an abnormal response by your body’s immune system.
Normally, the cells and proteins that make up the immune system protect you from infection. In people with Irritable Bowel Disease (IBD), however, the immune system mistakes food, bacteria and other materials in the intestine for foreign or invading substances. When this happens, the body sends white blood cells into the lining of the intestines, where they produce chronic inflammation and ulcers.
The broad facts of ulcerative colitis (UC) include the following:
- UC is a chronic disease that causes inflammation and sores, or ulcers, in the inner lining of only the colon (large intestine) and rectum. Crohn’s disease, which is often confused with UC, can affect any part of the gastrointestinal tract and all layers of the bowel wall.
- UC and Crohn’s disease are equally prevalent. About 700,000 Americans have been diagnosed with each condition.
- Men and women are equally likely to be affected. Most people are diagnosed in their mid-30s.
- Up to 20 percent of people with UC also have a close relative with the condition.
- UC is more common among white people of European origin and people of Jewish heritage.
- It’s estimated that 10 to 40 percent of UC patients will require surgery at some point during their illness.
- Ten years after diagnosis, the risk of colon cancer seems to be higher in UC patients than in Crohn's patients.
What exactly causes UC is not clearly understood, but genetic and environmental factors, and a defect in the immune system may all play a role.
Typical UC symptoms include:
- Diarrhea with blood and mucus present--this is the hallmark symptom of UC.
- Urgency to have a bowel movement
- Pain and cramping in the gut
- Loss of appetite
- Weight loss
Doctors tend to classify the severity of UC in a patient by how much of the colon is involved and the symptom pattern.
- Mild UC is classified as four diarrhea bowel movements (BM) per day with blood. About 50 percent of UC cases are considered mild.
- Moderate UC is four to six BMs per day with blood.
- Severe UC is more than six BMs per day with blood.
- Proctitis is UC that involves only the rectum.
- Proctosigmoiditis is UC that involves the rectum and the sigmoid colon.
- Left-sided UC involves the left side of the colon from rectum to the bend in the colon.
- Extensive UC or pancolitis affects the entire colon.
Typical tests used to detect UC include:
- Stool cultures
- Blood tests
- Barium x rays
- CT scans to look for inflammation
- The gold standard test is the biopsy of colon tissue taken during a sigmoidoscopy or a colonoscopy.
UC treatments include:
- Medications, such as aminosalycilates (or 5-ASA,) sulfasalazine (brand name: Azulfidine), and mesalamine (Lialda, Asacol, Canasa, Rowasa) help control inflammation.
- Corticosteriods, such as prednisone, methylprednisone, and hydrocortisone, also reduce inflammation.
- Immunomodulators, such as azathioprine (Imuran, Azasan), 6-mercaptopurine (Purinethol), and cyclosporine (Neoral, Sandimmun, Sandimmune) suppress the immune system.
- Infliximab (Remicade) is an anti-tumor agent prescribed for people who do not respond to other medications.
- Rectal enemas
- Surgery is sometimes needed to remove the rectum and part or the entire colon.
Goals of treatment in UC are to achieve remission of symptoms, to avoid flare-ups, and to improve a patient's quality of life. Often, patients will find they are able to achieve remission using only one UC medication. But other patients will need to try more than one, or use more than one medication at a time to achieve and maintain remission. UC patients also need to realize that these medications are not fast acting. It can often take two to four weeks, or sometimes longer, before a patient sees a response to the medication.