[Concept and differential diagnosis of irritable bowel syndrome].

The exact etiology of irritable bowel syndrome (IBS) is unknown. IBS is probably one of the commonest gastrointestinal disorders, but it has proved to be one of the most difficult conditions to diagnose. A proportion of patients give a strong history of stress-related or stress-evoked symptoms. In the past there has been a paucity of studies of this disorder because of difficulties in patient selection, choice of appropriate marker to be tested and the correlation of findings with the clinical presentation. A clear and precise definition of IBS is of most importance in the understanding of psychopathophysiological markers in this disorders.