The US Food and Drug Administration (FDA) approved the Gastric Emptying Breath Test (GEBT), a new non-invasive test to aid in the diagnosis of delayed gastric emptying, known as gastroparesis. The GEBT is manufactured by Brentwood, Tennessee-based Advanced Breath Diagnostics.

Current tests used to diagnose gastroparesis typically involve the use of a small amount of radioactive material or imaging equipment, so testing must be conducted in specialized outpatient centers. The GEBT can be used in broader settings.

“The GEBT is another option for aiding in the diagnosis of gastroparesis,” said Alberto Gutierrez, director of the Office of In Vitro Diagnostics and Radiological Health in the FDA’s Center for Devices and Radiological Health. “It can be performed in any clinical setting since it does not require the health care professionals administering the test to undergo special training or to take special precautions related to radiation emitting compounds.”  

Gastroparesis is a disorder that slows or stops the movement of food from the stomach to the small intestine when muscles in the stomach are not contracting properly. It is caused by damage to the vagus nerve that controls the muscles of the stomach and small intestine, often as a result of intestinal surgery, neurological diseases such as Parkinson’s disease and multiple sclerosis, or high blood glucose levels due to diabetes. If left untreated, gastroparesis can lead to problems such as severe dehydration due to persistent vomiting, difficulty managing blood sugar levels in people with diabetes, and malnutrition due to poor absorption of nutrients or a low caloric intake.

The GEBT, conducted over a four-hour period after an overnight fast, is designed to show how fast the stomach empties solids by measuring carbon dioxide in a patient’s breath. Patients have baseline breath tests conducted at the beginning of the test. They then eat a special test meal that includes a scrambled egg-mix and Spirulina platensis, a type of protein that has been enriched with carbon-13, which can be measured in breath samples.

Carbon-13 is a naturally existing non-radioactive form of the common element carbon-12. Both carbon-12 and a very small amount of carbon-13 are normally found in exhaled carbon dioxide. By adding carbon-13 to the test meal, the GEBT can determine how fast the stomach empties the meal by measuring the ratio of carbon-13 to carbon-12 collected in breath samples at multiple time points after the meal is consumed compared to baseline.

To support the safety and effectiveness of the GEBT, researchers conducted a clinical study using data from 115 participants who would typically undergo a gastric emptying test. All participants underwent testing with both the GEBT and gastric scintigraphy, the standard of care for measuring gastric emptying that requires ingestion of a test meal containing a radioactive material. Researchers compared diagnostic results from both the GEBT and scintigraphy and found that GEBT results agreed with scintigraphy results 73-97 per cent of the time when measured at various time points during the test.

No deaths or serious adverse events occurred during clinical studies. Some study participants reported nausea and stomach discomfort during the test. People with hypersensitivity to Spirulina, egg, milk or wheat allergens should avoid the GEBT. The test also should not be administered to people with certain lung diseases or conditions that cause small bowel malabsorption.