Pathophysiology of the irritable bowel syndrome - Reflections of today

Abstract

Irritable bowel syndrome (IBS) is a chronic gastrointestinal symptom complex defined by abdominal pain and disturbed bowel habits over 3 months within a period of 6 months, in absence of any identifiable organic pathology. Over the years, speculations of the pathophysiology of IBS has moved from elusive central nervous symptoms impinging on psychosomatic disease, to objective signs of intestinal fermentation with abdominal bloating and intestinal dysmotility. The specific subgroup of post-infectious IBS is of special interest since it opens the possibility of dysbiosis as the pivotal point for development of IBS in association with traveler's diarrhea or antibiotic treatment with ensuing dysbiosis and abdominal symptoms that may resolve over decades. The undefined disease mechanisms that take place within the gut seem responsible for the gut-brain signaling leading to activation of brain centers that drive the clinical picture of IBS, further modulated by the patient's social background and previous lifetime events.

Keywords: Dysbiosis; Irritable bowel syndrome; Motility; Rectal distension; Serotonin.