How is small intestinal bacterial overgrowth tested?
SIBO can be evaluated by breath testing and, more recently, small bowel culture. Although there are no definitive recommendations on the use of breath testing to diagnose SIBO, this test has become popular after evidence suggesting that IBS patients were more likely to have a positive SIBO breath test result. Breath testing should be used to evaluate patients for SIBO if they report bloating and distention as a significant complaint. Breath testing for SIBO can be performed with different substrates, although lactulose, a nonabsorbed carbohydrate, is most commonly used