The clinical picture of the irritable bowel can only be characterised through its symptoms. These were first set out in 1994 by the European Society of Gastrointestinal Endoscopy (ESGE) in the so-called Rome Criteria and were subsequently refined in 2000. Irritable bowel syndrome is diagnosed through an exclusion process, whereby the doctor must first exclude the possibility of all other disorders which display similar symptoms, such as bowel cancer, infections or chronic inflammatory bowel diseases (Crohn's disease, ulcerative colitis).
Lyon, 26 June 2000 - Irritable bowel syndrome is characterised by abdominal pain and a general feeling of discomfort, impaired digestion with diarrhoea, constipation or both of these symptoms in turn, as well as flatulence and mucous secretion in the stool. The ESGE set out two criteria for the diagnosis of irritable bowel syndrome:
1. Over the last 12 months the symptoms must have been present for more than 12 weeks (continuously or recurrently).
2. At least two of the following symptoms must have been experienced:
In the case of an irritable bowel the pain may be located in a number of different places (on the right or left side, in the upper or lower abdomen). It may vary from mild to severe in intensity so that patients are significantly restricted in their day-to-day activities. Additional problems in the gastrointestinal region are experienced in 25-50% of cases of irritable bowel syndrome. These include flatulence, heartburn, nausea and a sensation of abdominal bloating or fullness.
Irritable bowel syndrome accounts for 50% of digestive disorders which are treated by gastroenterologists and is thereby the most common reason for visits to gastroenterologists. It is also the second most frequent reason for work absenteeism. Women are particularly susceptible to this condition: surveys of adults in America and Europe have shown that 14 to 24% of all women suffer from an irritable bowel, as opposed to only 5 to 19% of men. There are no differences between people of different races - irritable bowel syndrome is also frequently diagnosed in Asia.
In the case of irritable bowel syndrome there is an increase in the sensitivity of the intestine, although no malignant diseases or changes in the structure of the intestine can be detected. This can lead to even normal bowel movements becoming painful (visceral hypersensitivity).
Disorders in bowel movements are also significant. The regular contraction and relaxation of the muscles in the intestinal wall (gastrointestinal motility and peristalsis) aids the transit of food. As it passes through the gastrointestinal tract, nutrients and water are extracted from the chyme and the contents of the intestine is thickened. If the food passes through the intestine too quickly, not enough water can be extracted from the chyme, leading to diarrhoea. On the other hand, if the transit of the food through the intestine is too slow, too much water is extracted and the stool becomes too hard, leading to constipation. Psychological factors such as stress can exacerbate the condition.
It is now believed that the condition is caused by a disorder in the serotonine balance in the intestine. The messenger serotonine and its receptors are partly responsible for the pain which is experienced, the regulation of the bowel movements and the production of mucous.
The first step in the exclusion process is to perform a blood count and to test the sedimentation rate of the blood. This provides information about inflammatory diseases (Crohn's disease, ulcerative colitis). In addition, the stools are examined for occult blood, possible infectious diseases or imbalances in the intestinal flora. The abdominal organs are examined by means of an ultrasound scan. An endoscopic examination must be made in order to exclude the possibility of either benign or malignant tumours. A lactose tolerance test provides information about whether the patient might be suffering from lactose intolerance. In some people an intolerance of milk and dairy products can lead to severe diarrhoea. If all the other possible causes of gastrointestinal disorders are excluded, the diagnosis is irritable bowel syndrome.
The most important thing is that the condition is explained in detail to the patient by the doctor. Care should be taken during conversations and by means of an endoscopic examination to reassure the patient that he/she does not have bowel cancer.
Medicinal therapy is based on the symptoms. If there is constipation, the doctor will prescribe medications which stimulate peristaltic movement. If the patient is suffering from diarrhoea, medications are recommended which slow down peristalsis. To alleviate the pain, medications are often prescribed which are anti-spasmodic and which relax the muscles in the intestine (spasmolysants, muscle relaxants).
The purely symptom-based therapy which has been used until now might be complemented in the future by new medications. Considerable hope is pinned on substances which work selectively on the serotonine system, normalising intestinal motility and alleviating the pain of visceral dilation.
A change in dietary habits can contribute to successful treatment. Generally speaking, fatty foods, alcohol, coffee and lactose, as well as gas-producing foods such as cabbage, onions, beans and the like should be avoided. Relaxation exercises, psychological treatment or hypnosis can also be very helpful in dealing with stress and anxiety.
References
Further information for the press only is available from:
Dr Anke Helten, Prof Dr René Lambert
Shandwick International München
Antonienstr. 1, 80802 Munich, Germany
Tel: +49 +89 383879-0 / -19 Fax: +49 +89 383879-38
ahelten@shandwick.de
(We will be happy to send information material on request via the ESGE)
