People with cystic fibrosis (CF) face persistent threats from pathogens including Pseudomonas aeruginosa (Pa), which grow in the lung’s mucus-clogged environment. Detecting these infections early is crucial, yet sputum-based tests have limitations. Scientists are turning to breath analysis as a noninvasive diagnostic alternative, measuring volatile organic compounds to signal infection.
Billy Boyle
Co-founder and Chief Executive Officer
Owlstone Medical
In this Innovation Spotlight, Billy Boyle, the co-founder and chief executive officer of Owlstone Medical, describes efforts to develop Breath Biopsy® for Pa detection. Data from initial studies will contribute to the Breath Biopsy VOC Atlas®, a detailed catalog of breath biomarkers that enhances researchers’ ability to detect disease-specific chemical signatures.
Why is Pa such a concern for people with CF?
CF is a genetic disease that impairs chloride transport, leading to thick, sticky mucus buildup in the lungs. This thick mucus creates an ideal environment for opportunistic pathogens such as Pa to thrive. Commonly found in moist environments, Pa poses a serious threat to people with CF, where it infects approximately 25 percent of patients and contributes to a rapid decline in lung function. Once established, Pa is extremely difficult to eradicate, often leading to chronic infection. Early detection is critical, but current methods—typically sputum-based cultures—can miss initial infections, particularly when patients cannot readily produce sputum.
How is Pa typically identified in patients with CF?
Pa is typically detected through sputum culture, a laboratory test that analyzes expelled lung secretions from the lower respiratory tract to identify bacteria, fungi, or other microorganisms that cause respiratory infections.
Why is there a need for a new Pa test, and how will a breath test benefit patients?
Sputum cultures are currently the gold standard for detecting lower respiratory tract infections, but it is increasingly difficult for people with CF to produce a sputum sample for culture. This is particularly true for a number of people with CF who benefit from drug therapies that reduce mucus in the lungs. A breath-based diagnostic test would offer a non-invasive, more patient-friendly alternative, enabling more consistent and frequent monitoring of lung infections during routine clinical visits, regardless of a patient’s ability to produce sputum.
What is Breath Biopsy® and how would the Pa breath test work?
Exhaled breath contains hundreds of volatile organic compounds (VOCs). VOCs can arise from exogenous sources, including the microbiome, food, smoking, pollution, and medication, and from endogenous sources within the body as the end product of metabolic processes. As such, they reflect both biochemical activity as well as environmental effects. Breath therefore represents a rich source of biological information that can be used to support disease research or to develop novel noninvasive diagnostic tests, such as for the early detection of lung cancer, cirrhosis, digestive disease, and infectious diseases including those caused by Pa.
Breath Biopsy® refers to the range of products and services that comprise a reliable platform to both collect and analyze VOCs in breath samples. VOCs are commonly quantified and identified using detailed chemical analysis tools such as gas chromatography combined with mass spectrometry.
In March 2025, we received investment from The Cystic Fibrosis Foundation to develop a breath-based test that can accurately detect Pa infection in patients with CF as well as, or better than, sputum culture. Another goal for the test will be to distinguish Pa from Staphylococcus aureus and other respiratory bacterial pathogens commonly found in the lower respiratory tract of people with CF.
Unlike traditional sputum tests, the new breath-based approach offers a noninvasive method to detect Pseudomonas aeruginosa infections in the lungs of cystic fibrosis patients.
iStock, quantic69
How are you developing this new test for chronic and new infection detection?
As there are a large number of clinical samples from people with established Pa infections, initial work will focus on detecting the presence of the infection. These samples have higher levels of VOCs, making it easier to prove this type of test could work. If this stage of the project is successful, additional work could be done to test whether this approach would detect new Pa infections.
What is the Breath Biopsy VOC Atlas® and how can it benefit researchers’ understanding of disease?
We have embarked on a project to better understand the composition of human breath both in terms of understanding the diversity present in a healthy population and the differences in different disease states. Through this work, we have developed the Breath Biopsy VOC Atlas®, a catalog of over 200 identified and quantified VOCs commonly found in exhaled breath. These compounds have undergone robust analytical comparison to background samples, enabling easy discrimination of chemicals seen in a breath sample from potential contaminants. The Atlas also provides insight and scientific context to identified compounds to enable the confident selection of candidate biomarkers related to a variety of diseases such as asthma, chronic kidney disease, chronic obstructive pulmonary disease, liver cirrhosis, and more.
We have now made specific data and functionality of the Atlas publicly accessible through our partnerships with the Gates Foundation and the US Food and Drug Administration.
