What Is It?

A number of infections and other conditions can cause the rectum to become irritated and inflamed, but few of them cause lasting symptoms. Ulcerative colitis, however, is a lifelong condition that begins with rectal inflammation and can worsen to involve much or all of the large intestine. Ulcerative colitis most often begins to cause symptoms between the ages of 15 and 40.

Research suggests that ulcerative colitis is genetic (inherited). The illness may begin with a breakdown in the lining of the intestine. Normally, the lining of the intestines keeps bacteria that normally live in the colon carefully sealed within the digestive "pipeline." As long as the bacteria are perfectly contained, it remains invisible to your immune cells and does not provoke a reaction. When the intestine's lining fails, bacteria that usually are harmless can activate your immune system. Ulcerative colitis is an autoimmune disease, meaning that the immune system attacks part of the body. In ulcerative colitis, cells from the immune system collect in the bowel wall and cause inflammation, injuring the bowel. Once the bowel inflammation has started, it can continue, even if the immune system stops being exposed to the bowel bacteria.

Ulcerative colitis affects the inner lining of the rectum and colon, causing it to wear away in spots (leaving ulcers), to bleed or to ooze cloudy mucus or pus. Sometimes, other parts of the body are affected by the inflammation, including the eyes, skin, liver, back and joints. One serious concern about ulcerative colitis is that it substantially increases the risk of colon cancer.

The disease is not contagious, even within families, so contact with another person cannot spread the disease.

Symptoms

The symptoms of ulcerative colitis vary. Some people with the disease have a burst of symptoms every few months. Others have symptoms either all the time or very rarely.

Typical symptoms include:

• Cramping abdominal pain, especially in the lower abdomen

• Bloody diarrhea, often containing pus or mucus

• A feeling that you have little warning before you need to have a bowel movement

• The need to wake from sleep to have bowel movements

Ulcerative colitis also may cause fever, fatigue, decreased appetite and weight loss. It also can lead to dehydration by causing you to lose fluids.