Two new studies validating hydrogen and methane breath tests were recently highlighted by Gastroenterology & Endoscopy News, with their results showing how breath tests can improve treatment plans of patients with common functional GI symptoms. In particular, the data from these studies show that breath tests can help distinguish between two IBS subtypes and characterize when there is a case of IBS vs. sucrose malabsorption.
Identifying Different Microbiomes in IBS Subtypes
The first study by researchers at Cedars-Sinai aimed to identify potential microbial drivers of the various IBS subtypes. Utilizing IBS-C (IBS constipation-predominant) and IBS-D (IBS diarrhea-predominant) subjects from 2 randomized controlled trials, the researchers collected their baseline breath carbon dioxide, methane, hydrogen, and hydrogen sulfide* levels using gas chromatography. They also analyzed the baseline stool microbiome composition of the subjects.
This study is the first to compare IBS phenotypes to microbiome and breath test compositions, and the results showed distinct gut microtypes linked to breath gas patterns in each IBS subtype. IBS-C had a higher association with methane and gut colonization of the methanogenic bacterium M. smithii. In comparison, higher breath hydrogen sulfide levels and a greater abundance of hydrogen sulfide-producing bacteria were seen in the IBS-D group.
Identifying these distinct microtypes for each subtype can increase the understanding of the gut microbiome and its relationship with different phenotypes of IBS. Additionally, a greater understanding of this relationship may pave the way for greater precision in developing targeted therapies based on the microbiome.
* Currently, no diagnostic technology on the market can test for H2S at levels of parts per billion (PPB) accomplished in a recent validation study on normal levels of H2S. CDI supports the continued research of hydrogen sulfide’s impact on the human body as well as best practices to collect, transport, and measure this trace gas as required.
Using Breath Tests to Distinguish Between IBS and Sucrose Malabsorption
The second cited trial completed by investigators at Weill Cornell Medical found that sucrose malabsorption often presents with symptoms similar to IBS, but hydrogen and methane breath tests may help distinguish between these two conditions.
According to the research report, the current gold standard for diagnosing sucrose deficiency (the cause of sucrose malabsorption) is a sucrose enzyme assay of duodenal biopsies obtained through an endoscopy procedure. In comparison, hydrogen and methane breath tests offer a non-invasive and more easily accessible screening method for sucrose malabsorption.
Frissora & Rao included 258 adults exhibiting symptoms of carbohydrate malabsorption in their trial, testing if the diagnoses obtained by hydrogen and methane breath tests and 13C-sucrose breath tests provided the same results as those from the gold standard. The study results showed that the two different breath tests detected an incidence of sucrose malabsorption of 34.4% and 40%, respectively, while 31% of the patients were determined to have sucrose intolerance through the gold standard. The high accuracy of the breath tests shows the promise of breath testing for distinguishing between IBS and sucrose malabsorption, despite their similar symptoms.
Advancing the Evidence Base for Hydrogen and Methane Breath Testing for Functional GI
Research continues to support using hydrogen and methane breath tests for improved diagnosis, better interventions, and optimized patient care plans. The two studies referenced validate the benefits of breath testing for distinguishing IBS subtypes and differentiating between IBS and sucrose malabsorption. Earlier this year, a study also validated that lactose and glucose breath tests can accurately diagnose intestinal methanogen overgrowth (IMO).
Don’t let your patients’ common functional GI issues go unchecked – learn more about using CDI’s breath testing as a diagnostic tool for your practice.