Crohn's disease

The main symptoms of Crohn's disease are abdominal pain or changes in bowel movements, and frequently diarrhoea, which can greatly affect quality of life.
A wide range of other symptoms are also possible:

• fever;
• night sweats;
• fatigue;
• blood in the stools;
• mouth ulcers;
• arthritis (inflammation affecting the joints);
• skin or eye lesions;
• nausea;
• loss of appetite or weight loss with deficiencies
• in a child with Crohn's disease, delayed growth or puberty.

The causes of Crohn's disease are multifactorial. It is an autoimmune disease, in which the immune system is too virulent and inappropriately attacks normal components of the intestinal flora. This leads to chronic inflammation in the digestive tract.

Known environmental risk factors include smoking, a diet rich in ultra-processed foods and regular use of non-steroidal anti-inflammatory drugs (NSAIDs). Genetic mutations may also be responsible for the onset of the disease.

All these factors can aggravate the excessive immune response targeting the body.

Diagnosis is based primarily on the doctor's analysis of the symptoms present and their duration and severity.

Colonoscopy, sometimes supplemented by gastroscopy, is the gold standard for confirming the diagnosis of Crohn's disease. It allows you to see inside the digestive tract, detect signs of inflammation and ulcers, and take biopsies* to confirm the diagnosis.

Other tests are necessary to make a diagnosis and assess the severity of the disease:

• a blood test;
• a stool culture, in particular to rule out infection;
• an imaging test such as an MRI* or an endoscopic capsule (to explore the extent of the disease in the small intestine).

The aim of the treatments available is to keep the disease in remission and restore the best possible quality of life.
Medicines are aimed at reducing inflammation and excessive immune response.
Certain severe complications of the disease, such as the formation of fistulas or stenoses (see ‘Evolution and possible complications’), may be treated by surgery. During surgery, the smallest possible segment of the inflamed digestive tract where the fistula or stricture is located can be removed. This surgery is effective, but it does not eliminate the disease, nor does it prevent the inflammation from persisting or spreading to other parts of the intestine.

During phases of remission, it is important that maintenance treatment is continued to avoid relapses.

Crohn's disease progresses in phases. If less than three months of remission elapse between two relapses, the relapse phases are said to be ‘early’. Frequent" relapses occur more than twice a year.

The inflammation can seriously damage certain parts of the intestine. This can lead to fistulas and strictures. The latter, which cause the wall of the intestine to thicken and the intestinal lumen to narrow, can prevent the passage of faeces to the rectum. If detected early, strictures can be treated with appropriate medical therapy. However, at a more advanced stage, this serious complication requires surgical treatment.

Urgent treatment is required in the event of perforation of the intestine, which can lead to peritonitis (acute inflammation of the peritoneum, caused by the spread of pus in the stomach).

Finally, people suffering from Crohn's disease of the large intestine have a greater risk than the rest of the population of developing colon cancer* after a few years. Screening by colonoscopy is therefore imperative.

There is as yet no way of preventing the onset of Crohn's disease. However, it is possible to take steps to limit the onset of flare-ups as much as possible. These include:

• stop smoking;
• monitor your lifestyle (regular physical activity and a balanced diet);
• identify foods with harmful effects;
• follow the prescribed treatment assiduously, even if the symptoms have completely disappeared (precisely because of the treatment).

It is important to consult your doctor if you repeatedly have watery, viscous stools, which often occur at night and are associated with abdominal pain or other symptoms (see ‘Symptoms of Crohn's disease’).

For people who have already been diagnosed with Crohn's disease, the warning signs are any symptoms or disorders that are out of the ordinary.

Hôpital de La Tour in Geneva is home to the Crohn's and Colitis Centre, a reference centre for monitoring chronic inflammatory bowel disease (IBD). It is the first centre in Geneva dedicated to IBD.