The Relationship of Fractional Exhaled Nitric Oxide(FeNO) and Acute Exacerbation of Childhood Asthma

Background: Asthma is a chronic inflammatory disorder in the airways. Measurement of FeNO( fractional exhaled nitric oxide ) is a non-invasive tool for measuring airway inflammation. The aims of this study was to investigate the relationship of FeNO and acute asthmatic exacerbation in children and to decide whether measurement of FeNO could predict acute exacerbation of asthma.

Methods: Thirty eight children with mild to moderate persistent asthma aged from 3 to 15 years were included. Patient’s data were based on out-patient records. FeNO was measured thorough chemiluminescence analyzer. Prospectively, the patients were followed for 6 month. The FeNO levels of asthma exacerbation group and non-exacerbation groups were evaluated.

Results: Mean age of the patients is 5.4 years. There were no difference of peripheral blood total eosinophil count, serum IgE, age, sex between asthma exacerbation group and non-exacerbation group. In the range of abnormal FeNO level (more than 10 ppb), there was significant difference of FeNO level between exacerbation group and non-exacerbation group (p=0.004). There was also significant correlation between FeNO level and acute asthma exacerbation (p=0.003).

Conclusions: Measurement of FeNO can be a useful tool to predict asthma exacerbation in mild to moderate persistent asthmatic children.