Abstract
Rationale: The majority of asthma exacerbations is caused by rhinovirus (RV) infection. Metabolomic assessment of exhaled Volatile Organic Compounds (VOCs) using an electronic nose (eNose) offers the opportunity to simplify and improve monitoring of asthmatics with exacerbations.
Hypothesis: We hypothesized that exhaled VOC-patterns change after experimental rhinovirus infection.
Methods: Patients with mild intermittent asthma (no ICS; age 22±3; M/F 4/5) and healthy controls (22±3; 1/13) underwent intranasal RV16 inoculation. Efficacy of inoculation was assessed by antibodies and PCR. Exhaled breath was collected using a standardized method 1 day before (visit 1), and 4 days (visit 2) and 2 months (visit 3) after exposure. Exhaled VOCs were measured by eNose (Cyranose 320) resulting in breathprints. Changes in breathprints were analyzed by principal component and mixed model analysis.
Results: 9/14 Asthmatics/healthy controls were included. Breathprint principal components (PC) changed significantly in asthmatics between visits 1 and 2 (p=0.010), and between visits 1 and 3 (p=0.015), but there was no change between visits 2 and 3. Breathprints of healthy controls did not change between any visit.
Conclusion: Rhinovirus infection changes exhaled VOC-patterns in asthmatics but not in healthy controls. This suggests that the change in exhaled VOC-pattern during and after RV infection in asthma may be used to monitor and predict exacerbations.
- © 2011 ERS