[Irritable bowel syndrome: an organic disease]

Irritable bowel syndrome (IBS) is a disorder of gut-brain axis interaction characterized by abdominal pain and alterations in stool form and/or frequency. The previous concept of a "functional disorder" has often been misinterpreted as "the opposite of organic" or "purely psychological," leading to stigmatization and even delegitimization of this condition. However, evidence supports that IBS has an underlying organic basis mediated by the complex interaction of multiple measurable and quantifiable pathophysiological alterations. These alterations include genetic predisposition, changes in the intestinal microbiota, visceral hypersensitivity, abnormalities in central pain processing, gastrointestinal motility disturbances, impaired intestinal barrier function, and environmental influences. Together, these elements are integrated through the gut-brain axis model, in which they form multiple positive feedback loops that initiate, exacerbate, and perpetuate IBS manifestations. In this review, we discuss in depth the underlying pathophysiological alterations of IBS to remind and raise awareness among healthcare professionals about the organic nature of this syndrome. Additionally, we summarize modern therapeutic approaches and their limitations in light of these organic alterations.