How to diagnose SIBO - Small Intestine Bacterial Overgrowth?

The first step in the diagnosis of small intestinal malabsorption and irritable bowel syndrome is the irritable bowel breath test (alternative name - SIBO breath test).

The irritable bowel breath test combines the detection of the two gases hydrogen and methane and thus allows to find out whether methane- and/or hydrogen-producing bacteria are the cause of the symptoms.

Furthermore, by assessing the time course of the breath gas test, a statement can be made about the position of the defective colonization in the small intestine.

This has very practical therapeutic consequences - depending on the site of colonization (upper or lower small intestine), a different diet is required; for methane-producing bacteria, for example, a different therapy regime applies.

The SIBO breath test is easy to perform and ideal as a home test. Sugar (synthetic or Glucose) is used as the test substance. Sugar cannot be digested and absorbed in the small intestine. Only intestinal bacteria are able to do this. Bacterial fermentation produces the gases hydrogen and methane, which are detected with the breath samples.

The Irritable Bowel Breath Test is the best breath test for detecting small bowel malabsorption and is based on international standards (2017 North American Breath Testing Consensus Guidelines).

After a first base test, a sugar liquid is drunk. A breath sample is obtained at 30 minute intervals. The sample tubes are sent to the laboratory for gas chromatographic analysis.

This has very practical therapeutic consequences - depending on the site of colonization (upper or lower small intestine), a different diet is required; for methane-forming bacteria, for example, a different therapy regime applies.