H. influenzae and S. aureus detection through breath analysis in PCD patients

In Primary Ciliary Dyskinesia (PCD), recurrent and chronic respiratory infections negatively affect disease progression. Current diagnostic tools for these infections are invasive or lack in sensitivity. An alternative is analysis of Volatile Organic Compounds (VOCs) in exhaled breath, which may contribute in the diagnostics of pulmonary pathogens (Joensen, O. <italic>et al</italic>. PLoS One, 2014;9:e115584). In this interim analysis we identified exhaled VOCs with gas chromatography-mass spectrometry in patients with PCD. The most discriminatory VOCs for the presence of H. influenzae and S. aureus in airway cultures were identified with sparse Partial Least Squares Discriminant Analysis (sPLS-DA). Exhaled breath analysis was performed in 54 patients [47% pediatric, 54% male, 17% CCD114 mutation, 17% DNAH5]. Two logistic regression models with three VOCs were able to significantly identify positive cultures of S. aureus or H. influenzae in respectively 87% and 86% of participants, as shown in figure 1. <fig><object-id>erj;64/suppl_68/PA4822/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig> With these results we show that VOCs can successfully identify the two most common pathogens in the airways of patients with PCD. In this study the diagnostic performance of exhaled VOC analysis appears to exceeds that of cough swabs, as compared to the gold standard (Fenn, D. <italic>et al</italic>. J Cyst Fibros, 2022;21:52-60). Future research with a longitudinal design and validation of findings in independent cohorts is necessary before clinical application.