The pathogenesis of bloating and visible distension in irritable bowel syndrome

Bloating is a common and bothersome complaint in irritable bowel syndrome, but its pathophysiology is largely unknown. Impaired control of gut motility probably combines with altered gut sensitivity to produce symptoms in patients with functional gut disorders, and the same sensory motor interaction may apply to bloating. The pathogenetic mechanism may involve trapping of intraluminal contents causing focal distension in a hypersensitive area. Furthermore, altered viscerosomatic reflexes in these patients distort abdominal wall muscular activity and contribute to objective abdominal distension even without net increment in abdominal contents. Conceivably, bloating is produced by a combination of mechanisms that may differ among individuals.