Nucleic acid detection and quantitative analysis of influenza virus using exhaled breath condensate

Non-invasive detection of Aspergillosis in ventilated patients: Galactomannan analysis in exhaled breath

This study evaluates the non-invasive diagnosis of Invasive Aspergillosis Pneumonia (IPA) in mechanically ventilated patients by measuring galactomannan (GM) in exhaled breath condensate (EBC). Utilizing a rat model and a novel EBC collection device, we compared GM levels in bronchoalveolar lavage fluid (BALF) and EBC, supplemented by cytokine profiling. Analysis of 75 patients confirmed the device's efficacy, with EBC-GM and BALF-GM showing high diagnostic accuracy (AUC = 0.88). The threshold of 0.235 ng/ml for EBC-GM achieved 92.8 % sensitivity and 66.7 % specificity, with a strong correlation (r = 0.707, P < 0.001) with BALF-GM. This approach offers a safe, effective alternative to invasive diagnostics, enhancing precision with IL-6 and TNF-α measurements. The number registered on clinicaltrails.gov is NCT06333379.

Metabolic profile of exhaled breath condensate from the pneumonia patients

PURPOSE OF THE STUDY

Exhaled breath condensate (EBC) is increasingly being used for disease diagnosis and environmental exposure assessment as a noninvasive method reducing the risk of exposure. The purpose of this study was to investigate the application of a new sample type of EBC in pneumonia by metabolomics and to explore differential metabolites and potential metabolic pathways.

MATERIALS AND METHODS

A case-control study was performed at the Peking University Third Hospital from August to December 2020. C-MS/MS analyses were performed on EBC samples using a UHPLC system.

RESULTS

Totally 22 patients with pneumonia and 24 healthy controls were recruited. Using untargeted metabolomics based on LC-MS/MS analysis, 25 kinds of differential metabolites were found. Through a comprehensive analysis of the pathways in which the differential metabolites were located, the key pathway with the highest correlation with the difference of metabolites was taurine and hypotaurine metabolism.

CONCLUSIONS

The study implicates that the hypotaurine/taurine metabolic pathway may play a role on the development of pneumonia through metabolism analysis on EBC and the 3-Sulfinoalanine may be used as a biomarker in the diagnosis of pneumonia.

Review of non-invasive detection of SARS-CoV-2 and other respiratory pathogens in exhaled breath condensate

In 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged to cause high viral infectivity and severe respiratory illness in humans (COVID-19). Worldwide, limited pandemic mitigation strategies, including lack of diagnostic test availability, resulted in COVID-19 overrunning health systems and spreading throughout the global population. Currently, proximal respiratory tract (PRT) specimens such as nasopharyngeal swabs are used to diagnose COVID-19 because of their relative ease of collection and applicability in large scale screening. However, localization of SARS-CoV-2 in the distal respiratory tract (DRT) is associated with more severe infection and symptoms. Exhaled breath condensate (EBC) is a sample matrix comprising aerosolized droplets originating from alveolar lining fluid that are further diluted in the DRT and then PRT and collected via condensation during tidal breathing. The COVID-19 pandemic has resulted in recent resurgence of interest in EBC collection as an alternative, non-invasive sampling method for the staging and accurate detection of SARS-CoV-2 infections. Herein, we review the potential utility of EBC collection for detection of SARS-CoV-2 and other respiratory infections. While much remains to be discovered in fundamental EBC physiology, pathogen-airway interactions, and optimal sampling protocols, EBC, combined with emerging detection methods, presents a promising non-invasive sample matrix for detection of SARS-CoV-2.