摘要目的 评估呼出气一氧化氮(FENO)在慢性咳嗽诊断和治疗中的临床应用价值.方法 根据中华医学会呼吸病学分会哮喘学组制定的咳嗽诊断与治疗指南(2009版),纳入卫生部中日友好医院呼吸内科门诊2010年1-6月明确诊断为慢性咳嗽的连续病例75例,其中咳嗽变异性哮喘(CVA组)29例,嗜酸粒细胞性支气管炎(EB组)19例,其他病因慢性咳嗽(胃食管反流性咳嗽、上气道咳嗽综合征等)27例,对所有患者分别进行FENO检测、诱导痰细胞分类计数、肺功能及激发试验、血清总IgE检测等,并评价咳嗽症状积分、生活质量问卷.按指南推荐的方案治疗4周后随访,再次进行上述评价.结果 CVA组的FENO值为(58±26)ppb,高于EB组的(36±18)ppb及其他慢性咳嗽组的(20±7)ppb,EB组高于其他慢性咳嗽组(F=28.2,P<0.01).相关性分析结果显示,治疗前慢性咳嗽患者的FENO与诱导痰嗜酸粒细胞比例(r=0.56)、与激发试验传导率下降的斜度(r=0.57)、与咳嗽症状总积分(r=0.61)均显著相关(均P<0.01).与血清总IgE水平、咳嗽生活质量问卷总分也具有相关性.CVA、EB组患者抗炎治疗后咳嗽缓解患者的基线FENO值为(63±42)ppb,高于未缓解患者的(28±13)ppb(t=3.91,P<0.01).抗炎治疗后FENO下降的比例与痰嗜酸粒细胞下降比例显著相关(r=0.53,P<0.01),与咳嗽症状积分下降比例显著相关(r=0.48,P<0.01).结论 呼出气一氧化氮与慢性咳嗽患者的嗜酸性气道炎症、气道反应性、特应质及咳嗽症状均存在相关性,在慢性咳嗽的诊治中具有一定的辅助价值.

abstractsObjective To evaluate the values of fractional exhaled nitric oxide (FENO) in the diagnosis and treatment of chronic cough. Methods Based on the protocol from The Chinese Respiratory Society guidelines for management of cough, 75 consecutive subjects with chronic cough and normal chest radiographs were recruited from the outpatient clinic of the Department of Respiratory Diseases in China-Japan Friendship Hospital from January to June 2010. All the patients accepted FENO tests, sputum cell counts, pulmonary function tests, bronchial hyperresponsiveness(BHR), serum IgE, cough symptom scores and Licester cough Questionnaire (LCQ) before and after treatment of 4 weeks. Results The final diagnosis of the subjects included 29 with cough variant asthma (CVA), 19 with eosinophilic bronchitis (EB) and 27 with other causes(Others). FENO levels in CVA(58±26)ppb were significantly higher than those in EB(36±18)ppb and Others(20±7)ppb, and the FENO levels in EB were higher than Others(F=28.2,P<0.01). FENO levels showed significant correlations with sputum eosinophils, BHR, cough symptom scores, non-specific IgE, and LCQ scores. The mean baseline FENO level of the subjects whose coughs were relieved after inhaled corticosteroid therapy was(63±42)ppb, higher than those of the non-responders (28±13)ppb(t=3.91,P<0.01). There were significant correlations between the percentage of FENO decrease and the percentage of sputum eosinophil decrease or the cough symptom score decrease. Conclusion FENO could be used as a inflammation marker of chronic cough because of its good correlation with sputum eosinophils, AHR, atopy, and cough symptoms. FENO also has a potential to predict the response of anti-inflammatory therapy because FENO decrease is correlated with the decrease of eosinophilic inflammation and improvement of cough symptoms.