Memphis, Tenn., Mar 19: A simple, noninvasive breath test may soon transform the way bacterial infections are diagnosed, according to a new study led by St. Jude Children’s Research Hospital and the University of California, San Francisco (UCSF). The research demonstrates that molecules broken down exclusively by infecting bacteria can be detected in exhaled breath, offering a rapid and affordable method to distinguish bacterial infections from viral illnesses or noninfectious inflammation. The findings were published today in ACS Central Science.
Currently, bacterial infections are confirmed through laboratory cultures, a process that can take days. The new approach uses a naturally occurring carbon isotope, carbon-13, to label mannitol, a sugar molecule metabolized only by bacteria, not by the body’s gut microbes. When administered, the carbon-13 mannitol is broken down by bacteria at the site of infection, producing labeled carbon dioxide that is exhaled and detected using inexpensive nondispersive infrared (NDIR) spectroscopy.
In proof-of-concept tests, the method successfully identified infections including myositis, bacteremia, pneumonia, and osteomyelitis. The research focused on pathogens common in clinical settings, such as Staphylococcus aureus, Streptococcus pneumoniae, Escherichia coli, and Salmonella enterica, highlighting its potential use even in immunocompromised patients where infections can be difficult to distinguish from inflammation.
“When patients present with nonspecific symptoms like pain or swelling, it can be challenging to determine whether the cause is infection or purely inflammatory,” said Kiel Neumann, PhD, co-corresponding author from the St. Jude Department of Radiology. “This breath test could serve as a quick screening tool, helping clinicians know whether a bacterial infection is present and reducing unnecessary antibiotic use.”
The study was co-led by David Wilson, PhD, UCSF, with Marina López-Álvarez, UCSF, as first author, and included a multidisciplinary team of researchers from St. Jude, UCSF, Ghent University, and other collaborating institutions.
“This work represents an important step toward an accessible, rapid, and safe diagnostic test for bacterial infections,” Neumann added. “Future clinical studies will explore how this technology can be implemented in everyday healthcare settings, including urgent care and emergency rooms.”
The study was supported by the National Institutes of Health (NIH), the Cystic Fibrosis Foundation, and the American Lebanese Syrian Associated Charities (ALSAC)
