Ulcerative colitis
What is ulcerative colitis?
Ulcerative colitis is one of 2 types of inflammatory bowel disease — a condition which causes the bowel (colon) to become inflamed and red. The other type of inflammatory bowel disease is known as Crohn’s disease.
Inflammatory bowel disease is a totally different condition from irritable bowel syndrome (IBS). In IBS, the functioning of the bowel is affected but it looks normal in appearance and there is no inflammation.
Ulcerative colitis and Crohn’s disease are long-term, chronic (ongoing) conditions which can flare up on and off throughout life.
What is the difference between ulcerative colitis and Crohn’s disease?
It can sometimes be difficult to distinguish between ulcerative colitis and Crohn’s disease, particularly in the early stages, because the symptoms are very similar. The major difference between the 2 is that in ulcerative colitis the inflammation affects only the inner lining of the bowel wall, whereas in Crohn’s disease the inflammation is of the full thickness of the bowel wall.
Also, the distribution of inflammation geographically within the gastrointestinal tract is different between the 2: ulcerative colitis affects only the large bowel (colon and rectum) and Crohn’s disease can affect any part of the gastrointestinal tract from the mouth to the anus.
With Crohn’s disease there may be patches of healthy bowel next to patches of the diseased bowel. The inflammation of ulcerative colitis, on the other hand, is a continuous inflammation, as opposed to the patchy inflammation of Crohn’s disease. About 15 per cent of people affected with ulcerative colitis will have pan-colitis where the whole colon is affected, and 85 per cent will have less extensive involvement of the colon, where only the rectum or the rectum and some of the adjacent colon is affected.
Who gets ulcerative colitis?
Ulcerative colitis affects people of all ages, but usually starts between the ages of 15 and 30 years. There is another (smaller) peak in the diagnosis of this disease between the ages of 50 and 70 years.
Although ulcerative colitis is uncommon in children, it can have more severe effects than in adults if it is not treated, such as delayed or stunted growth.
What are the symptoms?
Most commonly, the symptoms of ulcerative colitis include:
- abdominal pain, which is often crampy;
- a feeling of urgently needing to open the bowels;
- blood, mucus or pus in the stool;
- diarrhoea;
- fatigue and tiredness;
- weight loss; and
- loss of appetite.
People with ulcerative colitis may also develop other symptoms unrelated to the bowel. These can include mouth ulcers, skin problems, joint pains, and eye or liver problems. Sometimes, malabsorption of important nutrients can occur.
Most of the time many people with ulcerative colitis feel well and don’t have symptoms. This means the disease is not ‘active’ at this time, or can be said to be in remission. However, when the disease flares up and causes symptoms, this is known as a relapse.
Most of the time a ‘trigger’ for a relapse can’t be identified, although some people find that stress, infections, some medications or certain foods bring on an attack. It should be remembered that none of these is the cause of the disease itself.
Depending on where the inflammation occurs in the large bowel, ulcerative colitis can also be called proctitis (involving the rectum only), proctosigmoiditis or distal colitis (involving the rectum and sigmoid colon), or universal or pan-colitis, which means the entire colon is affected. Doctors don’t know why some people’s disease spreads to involve their entire colon yet in others the disease is confined to one area of it.
What causes ulcerative colitis?
Unfortunately the cause is still unknown despite intensive research. Causative factors that have been suggested include:
- genetic predisposition;
- infectious agents (bacteria and viruses);
- defects in the immune system; and
- environmental factors.
Some doctors suggest a combination of some or all of these factors may be involved. Psychological stress and food allergies are not thought to play a role in development of the disease, but they may aggravate symptoms in some people.
How is it diagnosed?
Ulcerative colitis is sometimes difficult to diagnose because its symptoms can be similar to other conditions such as bowel infections or irritable bowel syndrome. Most people with the disease will generally need a colonoscopy, sigmoidoscopy, or barium enema to confirm the diagnosis.
Colonoscopy and sigmoidoscopy are endoscopic examinations, in which a thin, flexible tube with a light on it (an endoscope) is passed into the rectum to allow the doctor to view the lining of your bowel. You will be lightly sedated during the procedure. The doctor may take a small piece of tissue from the lining of your bowel for examination under a microscope. This is called a biopsy.
You may also be given a barium enema, in which a solution containing barium is run into your rectum and X-rays of your intestine are taken. The barium outlines the digestive tract on the X-rays and should show up abnormalities of the bowel. Barium enemas are less commonly used to diagnose ulcerative colitis than endoscopy.
Blood tests can reveal whether you have anaemia or any vitamin or mineral deficiencies.
Can ulcerative colitis lead to cancer?
If you have widespread ulcerative colitis, your risk of developing colon cancer is higher than people who do not have ulcerative colitis. This is particularly true if you have had colitis for many years.
Your doctor will probably advise you to have regular examination by colonoscopy. Biopsies (small tissue samples) will probably be taken at the colonoscopy for microscopic examination to detect any changes in bowel tissue that might lead to cancer. Your doctor will advise you on how often you should have these examinations depending on how long you have had the ulcerative colitis.
Last Reviewed: 08 July 2009
