Irritable bowel syndrome (IBS) affects around 4% of the general population and remains the most common functional bowel disorder. It is defined by the Rome criteria as the presence of abdominal pain associated with transit disorders. The impact on quality of life and the associated costs make it a public health problem.
Visceral hypersensitivity is one of the functional markers of the disease and plays a part in the genesis of symptoms. It could therefore also be a therapeutic target to be explored. Diet and the intestinal microbiota are also part of the recognised pathophysiological mechanisms of this disease. Carbohydrates malabsorbed by the intestine are metabolised by the microbiota, which may contribute to the genesis of symptoms. Among these carbohydrates, fructose appears to be of particular interest. Its absorption capacity is limited, yet fructose consumption is increasing. Fructose malabsorption at a dose of 25 g is present in 22% of IBS patients. Fructose malabsorption is also associated with visceral hypersensitivity. However, the mechanism of this association remains unknown. In models of malabsorbed mice with visceral hypersensitivity, an increase in cholecystokinin was found in the terminal ileum and cecum, suggesting a potential role for this hormone in this model of IBS. However, the underlying mechanism remains poorly understood.
The objective is to determine if microbiota signature is specific of visceral hypersensitivity associated with fructose malabsorption in IBS patients.
60 patients with IBS will be included in the study in 4 groups:
1. n=15 patients with visceral hypersensitivity and fructose malabsorption
2. n=15 patients with visceral hypersensitivity and without fructose malabsorption
3. n=15 patients without visceral hypersensitivity and with fructose malabsorption
4. n=15 patients without visceral hypersensitivity and without fructose malabsorption
All patients will filled validated questionnaires and 4-days food diary. They will also have a urinary permeability test (lactulose/mannitol test) and collected stools samples for microbiota analysis.