Exhaled breath condensate eicosanoids and sputum eosinophils in asthmatic children: A pilot study

Cysteinyl leukotrienes (cys-LTs), LTB₄ and 8-isoprostane are increased in the exhaled breath condensate (EBC) from asthmatic patients. The aim of this study was to investigate whether the measurement of cys-LTs, LTB₄ and 8-isoprostane in EBC can reflect the level of airway inflammation assessed by induced sputum in asthmatic children sensitized to house dust mite (HDM) during natural avoidance of HDM allergens. Twelve children were evaluated at the time of admission (T0) and after 3 months of stay (T1) at the Istituto Pio XII (Misurina, Italian Dolomites 1756  m). Sputum eosinophil percentage and measurement of cys-LTs, LTB₄ and 8-isoprostanes in the breath condensate at T0 and T1 were evaluated. Eosinophil percentage in induced sputum was 8.5 ± 1.1% at T0 and 3.5 ± 0.4% at T1 (p = 0.011). Neutrophil percentage in sputum was 1.1 ± 0.5% at T0 and 1.5 ± 1.0% at T1 (ns). Cys-LTs mean level was 14.24 ± 4.53 pg/ml at T0 and 4.65 ± 0.68 pg/ml at T1 (p = 0.0125). LTB₄ level was 2.36 ± 0.19 pg/ml at T0 and 2.41 ± 0.23 pg/ml at T1 (ns). 8-Isoprostane level reduced from 17.47 ± 3.18 pg/ml at T0 to 7.36 ± 3.26 pg/ml at T1 (p = 0.003). This study show that exhaled cys-LTs and 8-isoprostane, as well as eosinophil percentage in induced sputum, are reduced after allergen avoidance in asthmatic children suggesting a potential application of EBC for the non-invasive evaluation of airway inflammation in asthma in allergic asthmatic children.