Overlap between GERD and IBS: Irrefutable but subtle

A substantial proportion of patients seen in gastroenterologic clinics complain of symptoms suggestive of functional derangement of both proximal and distal portions of the alimentary canal. Specifically, many patients with gastro-esophageal reflux disease also complain of the irritable bowel syndrome, but whether this association merely occurs by chance (owing to the high prevalence of these diseases in the general population) or rather reflects a common pathophysiologic basis is unknown. Recent evidence seems to partially support the latter hypothesis, because remarkable similarities have been identified in pathophysiologic studies performed on these apparently different subgroups of patients. This review highlights pathophysiologic features with a potential causative effect in both gastro-esophageal reflux and the irritable bowel syndrome including derangements of mucosal defensive mechanisms, mild inflammation, and visceral hypersensitivity. Indeed, interesting similarities exist in these putative pathophysiologic mechanisms, suggesting that the 2 pathologic conditions may represent different clinical manifestations of similar underlying causes. Ad hoc studies are necessary to prospectively evaluate this hypothesis. © 2007 Lippincott Williams & Wilkins, Inc.