Clinical Study Of Fractional Exhaled Nitric Oxide Level In Children With Asthmatic

Objectives:The aim of this study was to evaluate the assessment of asthmatic status and guidance of treatment by measuring the fractional exhaled nitric oxide (FeNO) levels in children with asthma in acute exacerbation and chronic persistent period. Comparing the difference of FeNO levels of asthmatic children in different disease severity groups and realizing the guiding function of FeNO levels for asthma treatment in order to evaluate the correlation of airway inflammation and FeNO.Methods:The study involved 67 asthmatic children (aged 5-12 years) from pediatric outpatient service in the people’s Hospital of Guangxi Zhuang Autonomous Region including 35 cases of mild exacerbation group and 32 cases of moderate-severe exacerbation group. The FeNO levels of all the asthmatic children were measured by using SV-eNO-01 Nano Coulomb Nitric Oxide Detector and Sunvou-D100 Nano Coulomb expiration Analyzer respectively in acute exacerbation and after inhaled corticosteroid treatment for four weeks. And be completed questionnaire of asthma control test at the same time.Results:1.FeNO levels of asthmatic children before treatment 41.52±27.42 ppb, were significantly higher than those of after treatment 19.00±13.98 ppb and control group 7.89±3.06 ppb (P<0.01). FeNO levels of asthmatic children after ICS treatment for four weeks were significantly higher than those of control group.2.FeNO levels of mild exacerbation group before treatment 26.49±3.99 ppb, were significantly higher than those of control group 7.89±3.06 ppb (P<0.01), FeNO levels of moderate-severe exacerbation group before treatment 57.97±29.17 ppb, were significantly higher than those of mild exacerbation group before treatment 26.49±13.99 ppb and control group 7.89±23.06 ppb (P<0.01).3. FeNO levels of mild exacerbation group after treatment 12.74±6.19 ppb were normal(P>0.05),however, moderate-severe exacerbation group 25.84±16.78 ppb lower than before treatment but significantly higher than those of control group 7.89±3.06 ppb (P<0.01).4. FeNO levels variation of asthmatic children before and after treatment were positively correlated with ACT scores, r=-0.71,-0.57,P=0.00。Conclusion:1.FeNO levels were increased when children in asthmatic exacerbation period, the levels were associated with the severity of exacerbation.2. FeNO levels were particularly increased of moderate-severe asthmatic children, after treatment, asthmatic children in chronic persistent period and the symptoms were controlled, FeNO levels were decreased but still unnormal, airway inflammation and airway hyperresponsiveness still exist.3. FeNO levels of asthmatic children were positively correlated with ACT scores.4. The variation of FeNO levels could reflect the state of airway inflammation, and use to asthma clinical diagnosis and treatment.