Definition Crohn's disease causes chronic inflammation of the gastrointestinal tract. It is one form of a condition known as inflammatory bowel disease
What is going on in the body? The cause of Crohn's disease is unknown. It is thought to be an autoimmune disease. This means that the body's immune system attacks a person's own body. This results in chronic inflammation of the gastrointestinal tract and other parts of the body.
What are the signs and symptoms of the disease? Crohn's disease may cause:
abdominal pain and tenderness
diarrhoea
fatigue
arthritis, or joint inflammation, which can cause joint pain and swelling
weight loss
skin rashes
vision problems
liver damage
anaemia, or low blood counts
malnutrition, due to damage of the intestines
mouth ulcers
What are the causes and risks of the disease? There is no known cause of Crohn's disease. Inherited factors are thought to play a role, as are immune system problems. The disease is more common among caucasians than blacks. Men and women are affected equally. Crohn's disease usually starts between 15 and 35 years of age.
What can be done to prevent the disease? There are no effective ways to prevent Crohn's disease.
How is the disease diagnosed? The disease is diagnosed through medical history, physical examination, and laboratory tests. There is no one test or feature of the disease that clinches the diagnosis. Colonoscopy is a procedure to examine the rectum, colon and bottom end of the small intestine. It involves passing a small telescope through the anus so that the rectum and large intestine can be seen directly. This procedure is very important if a person has long-term diarrhoea or bloody diarrhoea.
Laboratory studies may show anaemia, a low level of red blood cells. Laboratory studies may also show abnormal liver function, and low levels of certain vitamins and minerals. There may also be evidence of poor food absorption. Sometimes the diagnosis is made during surgery that is performed to fine the cause of severe abdominal pain.
What are the long-term effects of the disease? The course of Crohn's disease varies. It has a tendency to come and go, and includes periods without any symptoms. Both gastrointestinal and arthritis symptoms tend to recur.
Chronic bowel problems include the development of fistulas. A fistula is an abnormal passage or duct formed by the disease. It can connect two different areas of bowel or connect the bowel to the outer skin, or other hollow organ (such as bladder).
Other long-term effects include anal fissures, which are small tears, and pockets of pus near the rectum. An obstruction in the intestines or a hole or perforation in the intestines is also possible.
Five to 10% of Crohn's patients will die from the disease, mostly due to sepsis, an infection in the bloodstream. There is a slightly increased risk of bowel cancer in people with Crohn's disease.
What are the risks to others? Crohn's disease is not contagious. There is some tendency for the disease to run in families.
What are the treatments for the disease? The most commonly used medications are corticosteroids such as prednisone, and the drug sulfasalazine. Metronidazole is effective for treating infections in fistulas. Other drugs to suppress the immune system are used in severe cases in which the body is not responding to the standard medications. Some persons need extra vitamins, minerals, and salts. A healthy diet is essential for maintaining body weight. In severe cases, a person may need to be fed through an intravenous tube to improve their nutritional status.
Seventy percent of Crohn's patients will have surgery at least once. Surgery is most useful in treating complications. Procedures include the draining of abscesses, removing obstructed areas of intestine, and repairing fistulas.
What are the side effects of the treatments? There are many possible side effects from the drugs used to treat Crohn's disease. Corticosteroids can cause a host of side effects. These include:
weight gain
high blood pressure
acne
easy bruising
bone loss
increased blood sugar
cataracts
muscle weakness
emotional and psychiatric effects
Side effects of sulfasalazine include:
loss of appetite
headache
nausea
vomiting
diarrhoea
Metronidazole can cause:
a metallic taste in the mouth
mild stomach pain or cramps
dizziness
headache
nausea
diarrhoea
Persons taking metronidazole must avoid alcohol. Drinking alcohol while using this drug may cause intense vomiting and abdominal pain.
The most common risks from surgery include:
bleeding
infection
bowel perforation, or developing a hole in the bowel
What happens after treatment for the disease? Crohn's disease is a long-term disease with occasional flare-ups. There can be periods without any symptoms. However, the symptoms usually reappear.
How is the disease monitored? There is no specific test for monitoring the disease. Blood tests to assess inflammation are often used. Affected persons need to monitor their symptoms carefully. They should see their doctors if there are signs of infection or other changes in their symptoms or ability to function.
Author: Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
