Victorian researchers have developed a gas-sensing swallowable capsule device with high accuracy that could allow it to surpass breath testing as the benchmark for diagnosing gut disorders.
With intestinal gases such as hydrogen currently used for diagnosis of disorders including small intestinal bacterial overgrowth (SIBO) and carbohydrate malabsorption, biomedical engineers at RMIT University in Melbourne developed a telemetric gas-sensing capsule whose performance they compared against indirect measurement through breath testing.
The capsules and conventional breath test protocols were simultaneously evaluated in a single-blinded trial in 12 healthy subjects who were given doses of inulin or glucose after following a low FODMAPs diet.
Capsule measurements correlated closely with breath test hydrogen measurements after glucose and inulin ingestion, with a dose-dependent increase in concentration of hydrogen observed from the capsule following ingestion of inulin as low as 1.25g compared with >10 g for breath measurements.
“Specifically, the capsule measured >3,000 times higher concentrations of hydrogen compared to breath tests, resulting in a signal-to-noise ratio of 23.4 for the capsule compared to 4.2 for the breath test,” the researchers report in Alimentary Pharmacology and Therapeutics.
“Thus, increased gut accessibility and limiting physiological interferences provided by the capsule measurements potentially offer the ability to increase the selectivity and sensitivity in the clinical setting in comparison to breath testing,” they conclude.
The findings show that the capsule, currently being commercialised by Atmo Biosciences, can reveal information about gas production in the gut previously masked when measured indirectly through the breath, according to co-inventor, Dr Kyle Berean, a research fellow in materials science at RMIT.
“The rate of false positive and false negative diagnosis that breath tests give is a real problem in gastroenterology,” says Dr Berean, who is also Chief Technology Officer at Atmo Bioscience.
“Being able to measure these biomarkers at concentrations over 3,000 times greater than breath tests is quite astonishing.
The capsule has the potential to provide real time detection and measurement of hydrogen, carbon dioxides and oxygen in the gut, he adds.
The device is now being commercialised by Atmo, with further evaluation trials planned, said Dr Berean.