'Electronic nose' sniffs out Barrett's esophagus

Last Updated: 2020-02-28

By Will Boggs MD

NEW YORK (Reuters Health) - A new device called Aeonose can be trained to detect Barrett's esophagus in exhaled breath, researchers in the Netherlands report.

"Breath testing is able to distinguish between patients with or without Barrett's esophagus with a high sensitivity and reasonable specificity," Dr. Peter D. Siersema from Radboud UMC, in Nijmegen, told Reuters Health by email. "This is only the first study, and further studies are needed to evaluate/validate the Aeonose in primary care and/or in a dedicated screening program."

Volatile organic compounds (VOCs) in the exhaled breath result from metabolic processes in the body, including pathophysiologic processes such as inflammation or oxidative stress, and might serve as a biomarker for various diseases.

Dr. Siersema and colleagues evaluated the accuracy of exhaled VOC analysis using an electronic nose device for detection of Barrett's esophagus, compared with endoscopy and biopsy as the reference standard, in their proof-of-principle study of 129 patients with Barrett's esophagus, 141 patients with gastroesophageal reflux disease (GERD), and 132 controls.

The VOC profiles of patients with Barrett's esophagus differed significantly from the other two groups, the researchers report in Gut.

The device detected Barrett's esophagus in the total cohort with 91% sensitivity, 74% specificity, and overall discriminative accuracy of 91%.

In contrast, VOC analysis discriminated Barrett's esophagus patients from GERD patients with 64% sensitivity, 74% specificity, and 73% overall accuracy. It was even worse at discriminating patients with Barrett's esophagus from controls, with 57% sensitivity, 67% specificity, and 70% overall accuracy.

In sensitivity analyses, the device continued to show fair to good diagnostic accuracy for discriminating Barrett's esophagus from others in the subsets of individuals with hiatal hernia and those using proton-pump inhibitors (PPIs).

"The device could be used by primary-care physicians to detect Barrett's esophagus in patients with long-term reflux symptoms or on long-term anti-acid therapy," Dr. Siersema said. "Moreover, the device could also be used in a dedicated screening program in countries with a high incidence and/or prevalence of esophageal adenocarcinoma."

Dr. Kenneth K. Wang of Mayo Clinic, in Rochester, Minnesota, who studies Barrett's esophagus, told Reuters Health by email, "The problem with screening for Barrett's esophagus is low disease prevalence. The ways people have enhanced prevalence in the screening population is to select for GERD patients, male, over age 50, obese, family history of Barrett's esophagus, etc. This means that since this test may not separate GERD from Barrett's esophagus, it might not do well in an enhanced setting, but may be better as a screening tool for a more definitive test."

"There is potential for screening for Barrett's esophagus, but a population-based study needs to be done to find its role," he said.

The eNose Company supplied the Aeonose devices used in this study, but otherwise had no involvement and provided no additional funding.

SOURCE: https://bit.ly/32yu2AM Gut, online February 25, 2020.