评价Astograph乙酰甲胆碱激发试验对支气管哮喘的诊断价值

目的评价Astograph气道激发试验在诊断支气管哮喘(简称哮喘)中的价值。方法北京朝阳医院门诊就诊哮喘患者56例,非哮喘患者90例于激发试验前后均进行一次脉冲振荡及肺通气功能测定,分析激发试验前后患者的呼吸阻力、肺通气等的变化情况。结果①56例哮喘患者中激发试验阳性者52例,阳性率为92.9%(52/56),90例非哮喘患者中激发试验阴性者42例,阴性率为46.7%(42/90);哮喘组与非哮喘组脉冲振荡频率5 Hz及35 Hz时测得的呼吸阻力(R5、R35)、呼气峰流量(PEF)、第1秒用力呼气量(FEV1)、用力肺活量(FVC)的激发前后变化率及最小诱发累积剂量(Dmin)等差异均有统计学意义(P<0.05);②Dmin≤6 Unit作为阳性标准时其诊断哮喘的敏感性为71.2%,特异性为74.4%,准确性为53.0%;若同时以FEV1下降20%作为阳性标准,则可以显著提高其诊断哮喘的特异性。结论Astograph法气道激发试验有助于支气管哮喘的诊断,其中Dmin≤6 Unit作为阳性标准有较好的特异性及敏感性,若加做FEV1检查更能提高其特异性。

Evaluation of Role of Astograph Methacholine Provocation Test in Diagnosis of Bronchial Asthma

Objective To evaluate the role of Astograph methacholine provocation test in diagnosis of bronchial asthma. Methods Totally 56 asthmatics patients were recruited and 90 non-asthmatics patients was enrolled as control. All participants were asked to take Astograph methacholine provocation test. Spirometry and pulse oscillation measurements were conducted, and their breath resistance and spirometry parameters before and after the challenge were recorded and analyzed. Results 1) The provocative test of 52 participants out of 56 asthmatic patients were positive, the positive rate was 92.9%. In the 90 cases of non-asthmatic patients, the provocative test of 42 patients were negative, the negative rate was 46.7%; There was a significant difference in breath resistance at 5Hz(R5), breath resistance at 35 Hz(R35), Peak expiratory flow(PEF), forced expiratory volume in 1 second(FEV₁), forced vital capacity(FVC)(before and after the challenge), accumulated dose minimum induction(Dmin) between asthma group and non-asthmatic group(P<0.05); 2) The sensitivity, specificity, and accuracy of Dmin ≤6 Unit as cutoff for the diagnosis of asthma were 71.2% and 74.4% and 53.0%. The specificity of diagnosis increased significantly when Dmin combined with FEV₁ decreased by 20% as positive standard. Conclusion Astograph methacholine provocation test had good specificity and sensitivity in the diagnosis of bronchial asthma especially when the Dmin≤6 Unit as the cutoff value. Furthermore, its specificity was improved when FEV₁ was measured at the same time.