Millions of Americans suffer from undiagnosed gastrointestinal issues, often enduring lengthy and uncomfortable testing processes [[2]]. Now, a new non-invasive breath test is offering a possibly faster and more accurate path to diagnosis for conditions like lactose intolerance and small intestinal bacterial overgrowth (SIBO) [[1]]. The test, which analyzes exhaled breath for hydrogen and methane levels, promises to streamline digestive health assessments and is currently being expanded to potentially detect other illnesses, including dengue fever.
A new breath test is offering a potentially faster and more accurate way to diagnose digestive issues like lactose intolerance and bacterial overgrowth. The non-invasive procedure analyzes the air a patient exhales to detect levels of hydrogen and methane, indicators of how gut bacteria are interacting with sugars.
There are only two main restrictions for taking the test: individuals who have recently used antibiotics, for any reason, must wait four weeks before taking the breath test. The same four-week waiting period applies to those who have undergone a colonoscopy. “A colonoscopy essentially cleanses the gut, and it takes time for the gut microbiota to repopulate before we can accurately understand what’s happening,” explained Professor Domingues. Antibiotics have a similar effect, as they eliminate a portion of the intestinal bacterial population.
The test itself is straightforward. Patients simply breathe into a device, but technique is important. “When someone exhales, about 5 liters of air are released, but much of that air comes from the upper airways, the trachea and above,” said engineer Raphael Matsunaga. “I need the air that was deep within the alveoli of the lungs. Therefore, the breath needs to be continuous, without pausing, emptying the lungs as much as possible.” It’s the final part of the exhale, when a person feels nearly breathless, that the device analyzes for hydrogen and methane.
The entire process takes approximately two hours. After an initial breath sample, patients may be asked to consume a sugar like glucose, fructose, or lactose. Subsequent breath samples are then collected every 15 minutes to monitor gas levels. Higher levels indicate a larger population of bacteria and archaea metabolizing the sugar. Continued increases in gas levels with each dose often suggest an intolerance. The test boasts an accuracy rate exceeding 90%.
The test can be repeated to assess the effectiveness of lifestyle changes aimed at managing an intolerance. Overgrowth of hydrogen-producing bacteria typically requires a course of antibiotics, while an overgrowth of archaea is usually treated with a combination of two antibiotics.
The device is already streamlining the diagnosis of digestive problems and promises to be even more impactful for patients with intestinal disorders when sulfide hydrogen analysis is incorporated. Raphael Matsunaga and his healthtech company are also developing another breath test, in collaboration with the Universidade Estadual da Paraíba, to detect the dengue virus. The potential for a simple breath test to diagnose dengue infection is a promising development.
