Effects of Contagious Respiratory Pathogens on Breath Biomarkers

Area of Science:

• Biochemistry
• Microbiology
• Analytical Chemistry

Background:

• Exhaled volatile organic compounds (VOCs) offer non-invasive insights into host responses and pathophysiology.
• Metabolic profiling of respiratory infections is crucial for early pathogen detection and disease monitoring.

Purpose of the Study:

• To investigate the impact of common respiratory pathogens on exhaled VOC profiles in a real-world screening setting.
• To assess the diagnostic potential of VOCs for identifying infections like influenza and other respiratory illnesses.

Main Methods:

• Proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF-MS) analyzed breath samples from 479 individuals.
• Multiplex PCR identified respiratory pathogens (e.g., Haemophilus influenzae, Streptococcus pneumoniae, Rhinovirus).
• VOC profiles were correlated with PCR results and clinical symptoms.

Main Results:

• Exhaled VOC profiles were altered by the presence of Haemophilus influenzae, Streptococcus pneumoniae, and Rhinovirus.
• Changes in endogenous ketones, short-chain fatty acids, organosulfurs, aldehydes, and terpenes were observed.
• Few VOC concentration changes exceeded physiological variations, highlighting significant inter-individual differences.

Conclusions:

• Broad inter-individual variations in VOC profiles exist under real-life screening conditions.
• No unique VOC markers for infection were identified; only significant deviations from baseline are indicative.
• VOC analysis shows potential for infection detection, but requires careful consideration of individual variability.