The role of bile acids and their TGR5 receptor in irritable bowel syndrome and diarrhoea.

This commentary looks at recent findings relating to bile acids in patients with irritable bowel syndrome with diarrhoea (IBS-D). Bile acid diarrhoea is recognised to be a frequent, treatable cause of chronic diarrhoea, with a clinical picture which overlaps IBS-D. In the study - by Wei and colleagues, a large proportion of IBS-D patients were shown to have increased faecal bile acids, and an increase in primary bile acids, reflecting changes in bacterial metabolism. Expression of the colonic membrane bile acid receptor, TGR5, was associated with faecal bile acids and the severity of symptoms.