Objective: To study the correlation between fractional exhaled nitric oxide (FeNO) and airway reversibility in children with IgE-mediated asthma.
Methods: A total of 86 children, aged 6-14 years, who were initially diagnosed with acute attack of asthma from September 2016 to August 2018 were enrolled as subjects. According to the results of serum specific IgE, they were divided into IgE mediated group with 61 children and non-IgE mediated group with 25 children. According to the results of allergen detection, the IgE mediated group was further divided into four groups with one, two, three, and four or more positive allergens. FeNO and the parameters of pulmonary ventilation function before and after dilation test were measured. Pearson correlation analysis was used to evaluate the correlation of FeNO with each parameter of pulmonary function.
Results: The IgE mediated group had significantly higher FeNO than the non-IgE mediated group (P<0.05). FeNO increased with the increase in the number of positive serum specific allergens (P<0.05). In the IgE mediated group, FeNO level was positively correlated with the change in forced expiratory volume in the first second (FEV1) and the improvement in percentage of predicted FEV1 after medication in bronchial dilation test (r=0.655 and 0.473 respectively, P<0.05). The FeNO level was not correlated with FEV1, percentage of predicted FEV1, peak expiratory flow (PEF), change in PEF after medication, percentage of predicted PEF (PEF%pred), and improvement in PEF%pred after medication (P>0.05). In the non-IgE mediated group, FeNO level was not correlated with the above indicators (P>0.05).
Conclusions: FeNO level is associated with the degree of allergies. For children with IgE-mediated asthma, FeNO is positively correlated with airway reversibility, which has a certain value in the diagnosis of asthma, disease evaluation, and understanding of airway reversibility. For children with non-IgE-mediated asthma, FeNO cannot be used to evaluate airway reversibility. These two types of asthma should be treated differently.
目的: 探讨IgE介导的哮喘患儿呼出气一氧化氮（FeNO）与气道可逆性的相关性。
方法: 选取2016年9月至2018年8月初诊为哮喘急性发作的6~14岁患儿86例为研究对象，根据血清特异性IgE结果分为IgE介导组（n=61）及非IgE介导组（n=25），根据过敏原检测结果将IgE介导组进一步分为1、2、3种和4种及以上过敏原阳性组。检测FeNO水平及支气管舒张试验前后常规通气肺功能指标，采用Pearson相关性分析对FeNO与肺功能各项指标进行相关性分析。
结果: IgE介导组的FeNO水平明显高于非IgE介导组（P < 0.05）；FeNO水平随着血清特异性过敏原阳性种类的增加而增加（P < 0.05）；IgE介导组FeNO与支气管舒张试验用药前后第1秒末用力呼气量（FEV1）的改变量（△FEV1）和改善率（△FEV1% pred）呈正相关（分别r=0.655、0.473，P < 0.05），而与FEV1、FEV1占预计值百分比（FEV1% pred）、呼气峰流速（PEF）、用药前后PEF的改变量（△PEF）和改善率（△PEF% pred）、PEF占预计值的百分比（PEF% pred）无相关性（P > 0.05）；非IgE介导组FeNO与上述指标均无相关性（P > 0.05）。
结论: FeNO水平与过敏程度有关；对于IgE介导的哮喘患儿，FeNO水平与气道可逆性存在正相关，对哮喘的诊断、评估病情及了解气道可逆性有一定价值；对于非IgE介导的哮喘患儿，FeNO则不适用于间接了解其气道可逆性，两者需区别对待。