Assessment of hydrogen peroxide in breath condensate as an inflammatory marker in asthmatic children
Background: Asthma is a major global public health problem. Airway inflammation is the primary cause of development and progression of asthma. Activation of inflammatory cells induces a respiratory burst resulting in the production of reactive oxygen species, such as H2O2.
Objective: We sought to measure the concentration of H2O2 in exhaled breath condensate in asthmatic children and its correlation to asthmatic triggers, pulmonary function tests, treatment modalities and blood absolute white blood cell counts.
Methods: Fifty asthmatic and 35 healthy children were studied. Their ages ranged from 3-14 years. Exhaled H2O2 was measured using a colorimetric assay.
Results: In asthmatic children, there was a significant elevation of the mean H2O2 concentration compared to values in normal subjects( p<0.0001). Bad housing showed significant correlation to asthma severity and to number of acute asthmatic attacks. Basal spirometric pulmonary function tests, mean values showed no significant correlation to the level of H2O2 nor to treatment with inhaled steroids. Similarly, neither asthma severity nor the intake of inhaled steroids did show any significant correlation with H2O2 level.
Conclusion: Exhaled H2O2 was found significantly elevated in asthmatic children. Measurement of exhaled H2O2 may help to assess airway inflammation and oxidative stress in asthmatic patients.
Keywords: Hydrogen peroxide – H2O2 – exhaled breath condensate – asthma – children – oxidative stress – pulmonary function tests.