Innovative Breath Test Offers New Hope for Detecting and Monitoring Bacterial Infections

A groundbreaking non-invasive breath test has shown significant promise in the rapid diagnosis and monitoring of bacterial infections. Developed collaboratively by researchers at the University of California, San Francisco (UCSF) and St. Jude Children's Research Hospital, this innovative approach utilizes pathogen-specific metabolic tracers combined with a laser-based detection system to identify infections in real time. Presented by Dr. Marina Lopez-Alvarez at ESCMID Global 2025, the study demonstrates the test's effectiveness in preclinical models and outlines its potential clinical applications.

The fundamental principle behind this breath test is that pathogenic bacteria metabolize certain enriched compounds—such as ^13C-maltose and ^13C-mannitol—and produce detectable ^13C-labeled carbon dioxide in the exhaled breath, whereas mammalian cells do not. Researchers evaluated five bacterial species, including Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Enterococcus faecalis, and Enterobacter cloacae. They found that these bacteria metabolized specific compounds, leading to the generation of ^13C-CO2, which could be detected in the breath.

Importantly, the study validated that healthy mice did not produce ^13C-CO2 when given certain substrates like ^13C-maltose or ^13C-mannitol, confirming the specificity of the test for bacterial presence. In infected mice models, the detection of ^13C-CO2 correlated with bacterial infection, and a decline in ^13C-CO2 levels following antibiotic treatment with ceftriaxone indicated the test’s potential for monitoring treatment effectiveness.

This approach offers significant advantages over traditional diagnostics, which often rely on imaging or host immune response markers and can lead to delayed or inaccurate diagnoses. The use of bacteria-specific metabolites enables rapid, accurate detection of infections. Additionally, the laser-based detection system, based on integrated cavity output spectroscopy (ICOS), is notably more affordable and portable than conventional isotope ratio mass spectrometry (IRMS), making it suitable for point-of-care settings.

Professor David M. Wilson highlighted that the ICOS system could be available in emergency rooms or intensive care units for approximately $100,000 and is compact enough to fit in a carry-on bag. However, further research is necessary to ensure the test’s reliability in humans, as the next step involves confirming that healthy individuals do not produce detectable ^13C-CO2 from these substrates.

With existing clinical use in detecting Helicobacter pylori, researchers aim to expand breath testing to encompass a wider range of bacterial infections. This non-invasive method could revolutionize the approach to infection diagnosis and management, particularly in emergency and intensive care settings, by providing rapid, accurate, and real-time information.

Source: https://medicalxpress.com/news/2025-04-bacterial-infections.html