Robroeks et al studied metabolomics of volatile organic compounds (VOCs) in cystic
fibrosis patients and controls and revealed that metabolomics of VOCs in exhaled breath was reproducible and was able to
discriminate not only between patients and controls but also between patients with or without Pseudomonas colonization
(Robroeks et al., 2010). VOCs such as nicotinic acid have been found to be promising biomarkers for Mycobacterium tuberculosis
infections (Syhre et al., 2009).