Review article: Small intestinal bacterial overgrowth, bile acid malabsorption and gluten intolerance as possible causes of chronic watery diarrhoea

Aliment Pharmacol Ther. 2009 May 15;29(10):1069-77. doi: 10.1111/j.1365-2036.2009.03970.x. Epub 2009 Feb 15.


Background: Chronic watery diarrhoea is one of the most common symptoms prompting GI evaluation. Recently, new diagnostic considerations have emerged as possible factors in chronic diarrhoea.

Aim: To review available data regarding diagnosis and treatment of chronic diarrhoea with an emphasis on bacterial overgrowth and bile acid malabsorption.

Methods: A systematic search of the English language literature of chronic diarrhoea was performed focused on three possible aetiologies of diarrhoea: small intestinal bacterial overgrowth (SIBO), idiopathic bile salt malabsorption (IBAM), gluten responsive enteropathy.

Results: Recent studies suggest that SIBO and bile acid malabsorption may have been underestimated as possible causes of chronic watery diarrhoea. Gluten intolerance with negative coeliac serology is a contentious possible cause of watery diarrhoea, but requires further research before acceptance as an entity.

Conclusion: In patients with otherwise unexplained chronic watery diarrhoea, small intestinal bacterial overgrowth and bile salt malabsorption should be considered and investigated.

Publication types

  • Review

MeSH terms

  • Bacterial Infections / complications*
  • Bile Acids and Salts / metabolism*
  • Chronic Disease
  • Diarrhea / etiology*
  • Glutens / metabolism*
  • Humans
  • Intestine, Small / microbiology*
  • Malabsorption Syndromes / complications*


  • Bile Acids and Salts
  • Glutens