It may not be a boom trend, but more non-invasive diagnostic tests are coming to market as clinical laboratory tests that use breath as the specimen
Here’s a development that reinforces two important trends in diagnostics: non-invasive clinical laboratory assays and patient-self testing. Recently, the FDA expanded the clearance of one diagnostic test to allow patients to collect their own breath specimen at home under the supervision of the test manufacturer’s telehealth team.
The C-Spirulina Gastric Emptying Breath Test (GEBT) breath test from Cairn Diagnostics initially received federal Food and Drug Administration (FDA) approval in 2015. At that time, the test was required to be administered “at a physician’s office, a laboratory collection center, or in a tertiary care setting,” according to a 2016 news release.
Recently, however, the FDA announced it has “expanded the approval of the company’s 13C-Spirulina Gastric Emptying Breath Test (GEBT) to now include ‘at home’ administration under virtual supervision of Cairn Diagnostics.”
Self-administration of at-home tests by patients guided virtually by healthcare professionals is a major advancement in telehealth. But will this virtual-healthcare method be popular with both patients and their physicians?
Clinical Laboratory Diagnostics and Telehealth
Spurring a far greater acceptance of telehealth among patients and healthcare providers is one of the many ways the COVID-19 pandemic has impacted healthcare.
Cairn’s GEBT detects gastroparesis, a disease which, according to the NIH National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), affects 50 people in every 100,000. According to the CDC, it is also sometimes a complication of diabetes. Symptoms include nausea, heartburn, bloating, a feeling of fullness long after eating a meal, vomiting, belching, and pain in the upper abdomen, the NIDDK notes.
In people with gastroparesis—sometimes called “delayed gastric emptying”—muscles that normally move food from the stomach to the small intestine do not work as they should, and the food remains in the stomach for too long. The traditional diagnostic tool used to diagnose gastroparesis is scintigraphy. The patient consumes a meal that has radioactive material mixed in and the digestion process is observed using a nuclear medicine camera as the material is eliminated through the bowels.
Virtual Telehealth GEBT versus Scintigraphy
The telehealth process for Cairn Diagnostic’s Gastric Emptying Breath Test (GEBT) differs significantly from traditional scintigraphy testing. Once a physician prescribes the test, Cairn’s telehealth team contacts the patient to describe the virtual process. The team then ships the at-home test kit to the patient. To complete the testing, Cairn provides the patient with a web-based link to a secure audio/video platform.
During administration of the GEBT, a Cairn technician coaches the patient and supervises via video. Once the test is complete, the patient returns the breath samples to the CLIA-certified clinical laboratory by overnight courier. The test results are sent to the prescribing physician within 24-48 hours after the lab receives the samples.
Discovering New Uses for Breath as a Specimen for Clinical Laboratory Testing
For obvious reasons, patients prefer diagnostics that use specimens obtained noninvasively. GEBT is the latest in a growing list of diagnostic tests that use breath as a specimen.
For example, at Johns Hopkins clinicians employ breath testing to diagnose several conditions, including:
- Lactose intolerance,
- Helicobacter Pylori (H. Pylori),
- Fructose intolerance, and
- Bacterial overgrowth syndrome.
Each of these tests involves the patient consuming a particular substance, technicians capturing breath samples at certain intervals, and clinical laboratory personnel analyzing the samples to look for indicators of disease or intolerance.
New Types of Breath Tests
Breath samples are commonly used to diagnose gastrointestinal issues, but researchers also are seeking methods of using them to diagnose and monitor respiratory conditions as well.
In a recent study published in Nature Nanotechnology, scientists explored how breath can be used to monitor respiratory disease, noting that although breath contains numerous volatile metabolites, it is rarely used clinically because biomarkers have not been identified.
“Here we engineered breath biomarkers for respiratory disease by local delivery of protease-sensing nanoparticles to the lungs. The nanosensors shed volatile reporters upon cleavage by neutrophil elastase, an inflammation-associated protease with elevated activity in lung diseases such as bacterial infection and alpha-1 antitrypsin deficiency,” the researchers wrote.
Indeed, the search for new ways to use breath as a biological sample is being pursued by numerous groups and organizations. Owlstone Medical in the UK, for example, is developing breathalyzer tests for the detection of cancer as well as inflammatory and infectious disease.
“Exhaled breath is more than just air,” notes the company’s website. “It contains over 1,000 volatile organic compounds (VOCs) as well as microscopic aerosol particles, also known as respiratory droplets, originating from the lungs and airways.”
Analyzing breath allows for the:
- investigation of biomarkers of disease,
- patient stratification by phenotype,
- detection and monitoring treatment response, and
- measurement of exposure to harmful substances.
In fact, so many studies on using breath as a specimen have been conducted that in “Breath Biomarkers in Asthma: We’re Getting Answers, But What Are the Important Questions?” researchers Peter J. Sterk, PhD, Professor of Pulmonology at Amsterdam University Medical Centers, and immunity and respiratory medicine specialist Stephen J. Fowler, MD, FRCP, Professor of Respiratory Medicine at the University of Manchester in the UK suggested that systematic reviews are now feasible. They published their article in the European Respiratory Journal.
“Whilst we are still in this discovery stage it is time to refine our study designs so that we can make progress towards tailored clinical application,” they wrote. “Breathomics is perhaps at the ‘end of the beginning’ for asthma at least; it has a ‘sexy’ name, some promising and consistent findings, and the key questions are at least being recognized.”
Better for Patients, Clinicians, and Clinical Laboratories
Virtual telehealth tests, ordered by physicians, administered at home, and interpreted in CLIA-certified clinical laboratories, is a trend pathologists may want to watch carefully, along with the development of other tests that use human breath as the specimen.
Less invasive, more personalized diagnostic tools that can be administered at home are better for patients. When those tools also provide detailed information, clinicians can make better decisions regarding care. Clinical laboratories that approach the use of at-home tests creatively, and which can accurately and quickly process these new types of tests, may have a market advantage and an opportunity to expand and grow.