Electronic nose (E-nose) analysis of exhaled volatile organic compounds (VOCs) distinguishes pediatric patients (pts) with Cystic fibrosis (CF) from healthy controls (HC) and depicts disease status

Background: VOCs originate from metabolic pathophysiological processes at respiratory and systemic level. VOCs pattern has previously been analysed with E-nose on exhaled air; in CF it distinguished P.aeruginosa and A.fumigatus colonization. Aim: to evaluate exhaled VOCs pattern with E-nose (Cyranose320®)in HC and in CF pts; to compare exhaled VOCs in stable CF pts (StCF) and in pts with respiratory exacerbation (ExCF). Methods: a cross-sectional experimental study was approved by Verona Ethic Committee. Spirometry, N2multiple breath washout (MBW) and exhaled air collection were performed in 29 CF pts (age 12.56 ± 4.08; 23 StCF, 6 ExCF) and 15 HC (age 13.36 ±4.13). VOCs analysis was performed with Cyranose320®. The output data underwent multivariate analysis and Principal Component Analysis (PCA). Results: A number of E-nose sensors (S6-8, S10, S12, S21, S27, S28) significantly distinguished between HC and CF pts; also, StCF could be discriminated from ExCf (S6-8, S10, S12, S21, S27). For sensors distinguishing between HC and CF pts, AUC of ROC was more than accurate for S12 (0.85), good for S6-7, S21, S27 (0.73-0.76). PCA identified PC10, PC1, PC7 and PC2, which proved the best PC in predicting between HC and CF subsets. Spirometry distinguished HC from ExCF, but not from St CF, whereas N2MBW distinguished also StCF from HC. Conclusion: E-nose analysis of exhaled air samples distinguished HC from CF pts, and among CF pts, StCF from ExCF. N2MBW distinguished all 3 subsets, whereas spirometry only distinguished ExCF from HC. E-nose is a promising tool for clinical and research setting.