What is Crohn's Disease?
Crohn's disease is one of a group of bowel disorders that cause inflammation or ulceration in the small and large intestines. It mainly affects the large intestine and the lower part of the small intestine but can affect any part of the digestive tract from the mouth to the anus. Ulcerative colitis is a similar disease affecting the lower portion of the bowel (the colon and the rectum). Together these conditions are referred to as inflammatory bowel disease (IBD).
Crohn's disease is a chronic (long-lasting) condition that can improve or worsen at various times. People can experience long periods when they are free from symptoms - during these periods people are described as being in remission. The times when symptoms worsen are usually referred to as attacks.
An equal number of men and women are affected by Crohn's disease and it appears to run in some families. The illness can occur at any age but usually starts between the ages of 15 and 35 years. The number of young people with the disease is increasing.
What are the symptoms of Crohn's disease?
The most common symptoms include abdominal pain, diarrhoea and/or constipation. There may be rectal bleeding, which can lead to anaemia (low red blood cell count), which can in turn cause tiredness. Weight loss can also occur because food is not absorbed properly. Fever may occur as a result of infection in the bowel. Mouth ulcers are another common symptom of Crohn's disease.
Sometimes an attack may be severe enough to require hospital care.
What causes Crohn's disease?
The reason why Crohn's disease occurs is not yet fully known. However, many researchers now agree that there is a genetic element to the disease that can make certain individuals susceptible to interaction with environmental factors such as smoking, diet or stress. Such interaction results in chronic inflammation. One suggestion is that the disease may be activated by a bacterium in the intestines, but this has not been proven.
Research has shown that there is a family history of Crohn's disease in 25 to 40% of children affected by the disease.
Are there any tests to confirm the disease?
There are no specific tests to confirm the diagnosis of Crohn's disease but a blood test will confirm the number of platelets in your blood - an increased number suggests the presence of an inflammatory process somewhere in your body. The blood test will also show if you are anaemic. A stool sample may be examined to look for the presence of blood or for signs of infection.
X-rays will help to confirm the nature of the disease and the extent to which your digestive tract is affected. In some cases a barium x-ray will be used. For this you will be given barium as a drink or as an enema. Barium shows up white on x-ray film and can highlight any areas of inflammation and ulceration that may be present in your digestive tract.
You may also have a sigmoidoscopy or colonoscopy. These examinations involve passing a fibre-optic tube into the rectum or the lower bowel, respectively. The tube relays images to a video camera, allowing the doctor to see the degree of inflammation present.
A magnetic resonance imaging (MRI) scan may also be used to investigate Crohn's disease.
What treatment is available?
There is currently no cure for Crohn's disease but there are many treatment options available to help manage the symptoms. The treatment chosen will depend upon the severity of your symptoms. Medication can be given orally or introduced directly into the rectum via an enema or a suppository. In severe cases it may be given by injection.
Admission to hospital will be required for severe attacks. Steroids may be given by injection, together with fluids and electrolytes to combat dehydration. In most people the acute condition will settle within five to seven days and steroid tablets can then be given instead. For less severe cases, steroid tablets alone may be sufficient. Most patients will respond to treatment with steroids within four to six weeks and the dose will then be gradually tapered down over three to six weeks before stopping.
Some steroids are available as a rectal foam (eg, budesonide [Budenofalk® Rectal Foam] and hydrocortisone [Colifoam®]) or as enemas (eg, budesonide [Entocort® Enema] and prednisolone [Predsol® Enema]).
Creams or ointments containing a steroid and a local anaesthetic may also be given for use around the rectum if leakage occurs and the skin is sore.
Anti-inflammatory drugs known as salicylates may also be used to treat Crohn's disease, although their role in this condition is less well established than in ulcerative colitis. Salicylates licensed for use in Crohn's disease include mesalazine (eg, Asacol®, Octasa®) and sulfasalazine (eg, Salazopyrin®).
Immunosuppressant drugs such as azathioprine and ciclosporin may be of benefit in some people with Crohn's disease.
Adalimumab (Humira®) and infliximab (Inflectra®, Remicade®, Remsima®) are newer treatments that are given by injection. They are only used in specific patients who have not responded to steroids and/or immunosuppressants.
Vedolizumab (Entyvio®) is another option that may be used in patients with moderate or severe disease that has not responded to conventional treatment and/or immunosuppressants. It is given by intravenous infusion.
If drug therapy does not control the disease, surgery to remove the part of the bowel most affected may be required. However, this will not eliminate the disease completely and it may still recur in another section of the bowel. Surgery may also be necessary if an obstruction of the bowel or abscess occurs. Some people have their entire colon removed. If this is the case a colostomy will be created - this involves making a small opening in the right lower corner of the abdomen which is covered by a bag to collect the waste. The bag can be emptied periodically and some patients may find this easier to cope with than their original symptoms.
No special diet has been found to be beneficial in the management of Crohn's disease but a well-balanced healthy diet is as important for people with this disease as it is for anyone. Some people may find that their diarrhoea is made worse by milk, alcohol, hot spices, nuts or fatty foods. Try to avoid any foods which make your symptoms worse. Sometimes high-calorie liquid formulas are recommended if you need extra nutrition temporarily.
Further information available from:
Crohn's and Colitis UK
45 Grosvenor Road
Hertfordshire AL1 3AW
Tel: 01727 830038
Helpline: 0300 222 5700 (Mon, Tues, Wed, Fri 9-5pm; Thurs 9-1pm)
Fact sheet provided by MIMS
Date last reviewed: October 2016
What is Crohn's Disease?