Crohn’s disease is a chronic inflammation of the intestines that periodically will present itself as abdominal pain, diarrhoea and weight loss; in-between periods of no or little symptoms. The disease affects patients in their twenties and once the disease begins, it tends to be a chronic, recurrent condition with periods of remission and disease exacerbation. At times symptoms are scarce but at present there is no known cure for the disease. It primarily causes ulcerations in the small and large intestines, but can affect the digestive system anywhere between the mouth and the anus. The affected parts of the intestine are red and swollen and sores and bleeding ulcers can arise. When the inflammation heals scarred tissue may result in intestinal constrictions.
The cause of Crohn’s disease is not known, although it does seem to run in the family. One theory is that the body's immune system reacts to a virus or bacteria by causing ongoing inflammation in the intestine mucous membrane and deep tears (fistulas) in the intestine wall. The disease is more common in smokers.
Depending on how large part of the intestine is involved the symptoms will vary accordingly. Many patients will have felt weak symptoms for several years before a diagnosis. Symptoms vary from fever, persistent diarrhoea (loose, watery or frequent bowel movements), crampy abdominal pain (due to constrictions in the intestine), fatigue (since the body’s ability to absorb nutrients from food is reduced), loss of appetite with subsequent weight loss and a sense of sickness. Some patients may develop tears (fissures), which may cause pain and bleeding, especially during bowel movements. Inflammation may also cause a fistula to develop. A fistula is a tunnel that leads from one loop of intestine to another.
However, the disease is not always limited to the GI tract; it can also affect the joints, eyes, and skin. In certain cases it can also affect the liver and kidneys and there is an increased risk for blood clots and intestinal cancer. In general, though, people with Crohn's disease lead full or almost full, active, and productive lives. Several studies show that the life expectancy is not reduced.
In Sweden 500 patients a year are diagnosed with Crohn’s disease and it is believed that the prevalence is 30 000 people. It is slightly more common in women than in men.