What Is Crohn's Disease?

Crohn's and Colitis UK

Crohn’s Disease is a condition that causes inflammation of the digestive system or gut. Crohn’s can affect any part of the gut, though the most common area affected  is the end of the ileum (the last part of the small intestine), or the colon.

The areas of inflammation are often patchy with sections of normal gut in between. A patch of inflammation may be small, only a few centimetres, or extend quite a distance along part of the gut. As well as affecting the lining of the bowel, Crohn’s may also go deeper into the bowel wall. It’s one of the two main forms of Inflammatory Bowel Disease (IBD). The other is Ulcerative Colitis.

Crohn’s is a chronic condition. This means that it is ongoing and life-long, although you may have periods of good health (remission), as well as times when symptoms are more active (relapses or flare-ups).

What are the symptoms?

Crohn’s is a very individual condition – the symptoms vary from person to person, and may depend on where in the gut the disease is active. The symptoms range from mild to severe and can change over time, too. However, the most common are:

  • Abdominal pain and diarrhoea
  • Tiredness and fatigue
  • Feeling generally unwell or feverish
  • Mouth ulcers
  • Loss of appetite and weight loss
  • Anaemia (a reduced level of red blood cells)

Who gets Crohn’s Disease?

We think Crohn’s Disease affects at least 115,000 people in the UK and millions more worldwide. The condition is more common in urban areas and in northern developed countries – although it’s on the increase in developing nations.

Crohn’s is also more likely to appear in white people of European descent, especially those descended from Ashkenazi Jews (who lived in Eastern Europe and Russia). The disease can start at any age, but usually appears for the first time between 10 and 40. Surveys suggest that new cases of Crohn’s are being diagnosed more often, particularly among teenagers and children. It’s slightly more common in women than in men, and also in smokers.

What causes it & is there a cure?

Despite a lot of research, we still don’t know exactly what causes Crohn’s Disease. However, over the past few years major advances have been made, particularly in genetics. We now believe that Crohn’s is caused by a combination of factors;

  • the genes you are born with,
  • plus an abnormal reaction of your immune system to certain bacteria in your intestines,
  • along with an unknown trigger that could include viruses, bacteria, diet, smoking, stress or something else in the environment.

There isn’t a cure at the moment, but drug treatment and sometimes surgery can do a lot to give long periods of relief from symptoms.

What treatments are there for Crohn’s?

Treatments may be medical, surgical or a combination of both. If your condition is mild, not having any treatment might even be an option. Some people may also find relief from their symptoms by altering their diet or going on a special liquid diet.

But your treatment will ultimately depend on the type of Crohn’s you have and the choices you make in discussion with your doctor.

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