Small Intestinal Bacterial Overgrowth (SIBO)

LAB TESTING

Small Intestinal Bacterial Overgrowth is, as its name implies, abnormally high levels of bacteria in the small intestine. SIBO can co-exist with irritable bowel syndrome (IBS).

SIBO is detected by hydrogen- and methane-gas breath tests. However, it should be noted that the current best SIBO breath tests have a 20-30% false positive and false negative rate, which affects the test’s reliability and reproducibility.

This test itself involves swallowing a sample of a sugar substrate (glucose). In response to glucose, the bacteria in the small intestine produce abnormally high levels of hydrogen and/or methane as byproducts. These gases are then measured and analyzed through breath collection. 

Testing for SIBO may be indicated when a person has the following risk factors:

• Taking PPIs (proton pump inhibitors) long-term

• Diabetes, especially if experiencing gastroparesis

• Hypothyroidism

• Celiac disease

• Neurological disorders like Parkinson’s Disease

• Motility disorders

• Some autoimmune conditions like inflammatory bowel disease, scleroderma, and lupus