高渗盐水支气管激发试验预测运动性哮喘的临床价值

Clinical value of hypertonic saline bronchial provocation test in predicting exercise-induced asthma

目的探讨高渗盐水支气管激发试验预测运动性哮喘（EIA）的临床价值。方法对在本院就诊的36例年轻男性哮喘患者进行支气管激发试验，依次进行高渗盐水激发试验（吸人4．5％高渗盐水）、运动激发试验（间隔24h）及乙酰甲胆碱（MCh）激发试验，并对3者间的相关性进行评价。结果对高渗盐水有高反应性（HS—AHR）的哮喘患者运动后1秒用力呼气量（FEV。）下降的最大值显著高于无HS—AHR患者，运动与高渗盐水所诱发的AHR严重程度具有显著相关性。在预测EIA的价值上，高渗盐水激发试验比MCh激发试验具有更高的特异性（71．4％：42．9％）。当临界值MCh—PC20≤1ms／mL（中度～重度AHR）时，二者对于判断EIA的特异性具有可比性（71．4％：71．4％），但高渗盐水激发试验对于判断EIA的敏感性低于MCh试验，同时，MCh试验阳性似然比高于HS激发试验，而阴性似然比却更低。结论在预测EIA的价值上，高渗盐水激发试验比MCh激发试验具有更高的特异性，但敏感性较低，而在中度AHR的临界值方面，MCh激发试验能更好地预测EIA。

Objective To explore the clinical value of hypertonic saline bronchial provoca- tion test in predicting exercise - induced asthma （EIA）. Methods 36 young male patients with asthma were conducted with bronchial provocation tests, including hypertonic saline provocation test （ inhalation of 4.5% hypertonie saline）, exercise provocation test （interval of 24 hours） and methacholine （MCh） provocation test. Correlations among 3 groups were evaluated. Results The maximum forced expiratory volume in one second （ FEV1 ） after exercise in asthma patients with hypertonic saline airway high reactivity （HS -AHR） was significantly higher than that in asthma patients without HS -AHR, and the exercise was evidently associated with degrees of AHR induced by hypertonie saline. Specificity of HS provocation test in predicting EIA was 71.4%, which was significantly higher 42.9% in the MCh test. When MCh -PC20 critical value ≤ 1 mg/mL （moderate/severe AHR）, specificity for EIA differentiation in both tests was 71.4%, but excitability for EIA differentiation in HS provocation test was lower than that in the MCh test. Meanwhile, the positive likelihood ratio of MCh test was higher than HS provocation test, and the negative likelihood ratio was lower than HS provocation test. Conclusion In the prediction of EIA, HS provocation test is proved to be more specific than MCh test, but excitability was lower than MCh test. MCh test may be more useful for predicting EIA in the aspect of AHR critical value.