呼出气一氧化氮浓度测定对变应性鼻炎合并下气道高反应性或哮喘的预测及辅助诊断价值研究

摘要

目的 探讨呼出气一氧化氮浓度(FeNO)测定对变应性鼻炎合并无症状的下气道高反应性患者或非急性发作期(慢性持续性)哮喘患者的预测及诊断价值.方法 对广州医科大学附属第一医院呼吸科收治的20例变应性鼻炎患者、15例变应性鼻炎合并无症状的下气道高反应性患者及20例变应性鼻炎合并非急性发作期(慢性持续性)哮喘患者(年龄18 ～50岁)进行FeNO测定、鼻腔灌洗细胞分类计数、诱导痰细胞分类计数以及乙酰甲胆碱支气管激发试验,分析各项指标的分布特点及相关性,探讨FeNO测定对变应性鼻炎患者合并无症状支气管高反应性(BHR)或非急性发作期(慢性持续性)哮喘的预测及下气道炎症的评估.结果 FeNO值的中位数和四分位间距在单纯变应性鼻炎组、变应性鼻炎合并无症状下气道反应性增高组、以及鼻炎合并哮喘组分别为24.0(15.5,35.5) pg/L、46.5(35.0,63.0) pg/L和61.5(39.0,75.0) pg/L,3组间差异具有统计学意义(P＜0.01).以测定的FeNO值为标准对变应性鼻炎患者下气道高反应性进行判断,绘制ROC曲线(AUC=0.842,P=0.002),以34.0 pg/L为截断点则敏感度为75.0％,特异度为73.7％.以FeNO值对变应性鼻炎合并哮喘诊断的ROC曲线(AUC=0.887,P=0.000),FeNO值取41.0 pg/L时对变应性鼻炎合并哮喘诊断的敏感度为75.0％,特异度为83.1％.诱导痰中嗜酸性粒细胞(EOS)在单纯变应性鼻炎组、变应性鼻炎合并无症状下气道反应性增高组以及鼻炎合并哮喘组分别为(2.43±3.56)％、(7.36 ±4.98)％及(18.5％±11.26)％,3组间差异具有统计学意义(P＜0.01).结论 变应性鼻炎患者可伴有一定程度的下气道炎症,且与下气道高反应性密切相关.FeNO测定简便、稳定,对变应性鼻炎患者合并下气道高反应性或哮喘具有良好的预测和辅助诊断作用.%Objective To investigate the predictive and diagnostic value of fractional exhaled nitric oxide (FeNO) in patients with allergic rhinitis accompanied with asymptomatic bronchial hyperresponsiveness (BHR) or chronic persistent asthma.Methods FeNO,nasal lavage,eosinophils (EOS) in induced sputum and methacholine bronchial provocation test (BPT) were performed in 20 patients with allergic rhinitis (AR) (male/female:9/11,aged 18-50 years),15 patients with AR and asymptomatic BHR (AR + BHR)(male/female:7/8,aged 18-50 years) and 20 patients with AR and chronic persistent asthma (AR + asthma)(male/female:8/12,aged 18-50 years).Correlation between FeNO and EOS was analyzed.Receiver operating characteristic (ROC) curve was applied to evaluate the predictive and diagnostic value of FeNO.Results The median and interquartile range of FeNO values in AR,AR + BHR and AR + asthma were 24.0 (15.5,35.5)pg/L,46.5 (35.0,63.0) pg/L and 61.5 (39.0,75.0) pg/L,respectively,with statistically significant difference among the groups (P ＜ 0.01).ROC curve was obtained using FeNO values to assess the diagnosis values.In AR + BHR group,the area under curve (AUC) was 0.842 (P =0.002) ;the sensitivity was 0.750 and specificity was 0.737 ;while the cut-off value was set as 34.0 pg/L.For the diagnoses of AR + asthma,AUC was 0.887 (P =0.000) ; the sensitivity was 0.750;and the specificity was 0.831,when taking 41.0 pg/L as the cut-off value.The percentages of EOS were (2.43 ± 3.56) ％,(7.36 ± 4.98) ％,(18.58 ± 11.26) ％ in AR group,AR + BHR group and AR + asthma group,respectively,with statistically significant differences among the groups (P ＜ 0.01).Conclusion Lower airway inflammation might exist in some extent in patients with allergic rhinitis.The mcasuremcnt of FcNO is simple and stablc with reliable predictive and diagnostic value for patients with allergic rhinitis accompany with BHR and chronic persistent asthma.