Increased inflammatory mediator in exhaled breath condensate from asthmatic children

Purpose: There has recently been increasing interest in the use of exhaled breath condensate (EBC) as a simple noninvasive means for understanding the physiology of asthma. The aim of this study was to evaluate the levels of leukotriene B-4 (LTB4) and eosinophil cationic protein (ECP) in the EBC of asthmatic children. Methods: We measured LTB4 and ECP levels in EBC from children aged 6-14 years, including healthy children ( n= 25) and asthmatic children (n= 25). We also measured serum LTB4 and serum ECP. Pulmonary function tests and methacholine challenge tests were performed on all subjects. Results: Exhaled LTB4 levels were increased significantly in patients with asthma compared to normal subjects (7.1 +/- 3.7 pg/mL vs. 2.2 +/- 1.7 pg/ mL, P< 0.05). Serum LTB4 levels were not significantly different in patients with asthma compared to normal subjects (674.7 +/- 484.1 pg/mL vs. 487.1 +/- 272.0 pg/mL, P= 0.156,) and no significant correlations were found between exhaled and serum LTB4 concentrations in children with asthma (r= 0.052, P= 0.758). Exhaled ECP levels were not significantly different in patients with asthma compared to normal subjects (P= 0.419). Serum ECP levels were significantly increased in patients with asthma compared to normal subjects (44.37 +/- 32.14 mu g/ L vs. 16.40 +/- 13.23 g/mu L, P= 0.001). Conclusion: We found significantly elevated LTB4 levels in the EBC of asthmatic children. Our results suggest that EBC may be one of the supportive tools to measure airway inflammation in children with asthma.