Irritable Bowel Syndrome
A chronic disorder of gut-brain interaction diagnosed positively from abdominal pain related to defaecation or altered stool pattern, once relevant red flags and targeted tests have been addressed.
Definition
Irritable bowel syndrome is a chronic disorder of gut-brain interaction characterised by abdominal pain related to defaecation or altered stool frequency/form, with associated bowel symptoms and no better explanation after appropriate targeted assessment.
First principles
IBS is a disorder of gut-brain interaction, not simply a diagnosis of exclusion
IBS reflects altered gut motility, visceral sensitivity and bidirectional gut-brain signalling. Stress, meals, prior infection and dietary factors may amplify symptoms, but IBS is not imaginary or purely psychological. There is no single structural lesion that explains the syndrome, so a confident positive diagnosis and a coherent explanation are more useful than repeated low-yield investigations.
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