Abstract: Objective To explore the value of fractional exhaled nitric oxide(FeNO),total immunoglobulin E(tIgE) and blood eosinophils(EOS) in the diagnosis of asthma in children.Methods A total of 46 children with bronchial asthma,who were diagnosed in the First People′s Hospital of Xiangtan city between April to October 2021,were included in the observation group,and 41 children without bronchial asthma were included in the control group.The results of FeNO,tIgE,blood routine examination and pulmonary function test of the two groups were collected,and the levels of FeNO,tIgE and EOS and FEV1% were compared between the two groups.Correlation analysis was also conducted.The receiver operating characteristic curve (ROC curve) was drawn to analyze the diagnostic efficacy of FeNO,tIgE and EOS for childhood asthma.Results The levels of FeNO,tIgE and EOS in the observation group were significantly higher than those in the control group,while the forced expiratory volume in the first second as a percentage of predicted Value(FEV1%) in the observation group was lower than that in the control group(all P<0.05).In the observation group,FeNO,tIgE,and EOS levels were negatively correlated with FEV1%,while tIgE level was positively correlated with FeNO level (all P<0.05).There was no correlation between EOS level and FeNO(P>0.05).The optimal cut-off values of FeNO,tIgE and EOS for diagnosis of child asthma were 19.5 ppb,89.1 IU/mL,and 0.585×109/L,respectively.The specificity and sensitivity of the three indexes combined together for diagnosis of asthma in children were 84.8% and 87.8%,respectively,which were higher than the values of each single index.Conclusion The elevated levels of FeNO,tIgE and EOS are closely related to the occurrence of childhood asthma.All of them can be used as important diagnostic indexes for childhood asthma.Combination of the three indexes can improve the efficiency and accuracy of the diagnosis of childhood asthma.

Key words:

Asthma, Fractional exhaled nitric oxide, Immunoglobulin E, Eosinophils, Children