Xpert结核分枝杆菌/利福平试验对儿童活动性结核病的诊断价值及影响因素

Diagnostic value and influencing factors of Xpert MTB/RIF assay for active tuberculosis in children

目的探讨Xpert结核分枝杆菌/利福平试验(Xpert)对儿童活动性结核病的诊断价值及影响因素。方法比较结核菌素试验(TST)、γ-干扰素释放试验(IGRAs)和Xpert对不同年龄、不同类型儿童活动性结核病的诊断效能,以及比较不同标本检测Xpert的诊断效能。结果共纳入活动性结核病患儿231例,非结核病患儿216例。Xpert灵敏度为62.78%,显著低于IGRAs的78.32%(P<0.05);特异度为100%,显著高于其他两种方法(P<0.001)。≤5岁组Xpert灵敏度为74.71%,高于IGRAs的67.47%(P>0.05);>5岁组Xpert灵敏度为58.26%,显著低于IGRAs的84.62%(P<0.001)。Xpert对肺结核的灵敏度显著高于肺外结核(P<0.001)。不同标本间Xpert的灵敏度比较差异有统计学意义(P<0.05),肺泡灌洗液最高。疑似肺结核患儿,肺泡灌洗液检测Xpert的灵敏度显著高于痰液(P=0.012)。疑似肺结核合并肺外结核患儿,呼吸道标本检测Xpert的灵敏度显著高于非呼吸道标本(P=0.004)。结论Xpert可用于诊断儿童活动性结核病,尤其适用于5岁以下儿童、肺结核和肺泡灌洗液,对于肺结核合并肺外结核应优先检测呼吸道标本。

Objective To investigate the diagnostic value and influencing factors of Xpert MTB/RIF assay(Xpert)for active tuberculosis in children.Methods The sensitivity and specificity were compared among tuberculin skin test(TST),interferon gamma release assays(IGRAs)and Xpert among different ages and types of active tuberculosis in children,and the sensitivity of Xpert was compared among different types of specimens.Results A group of 231 children with active tuberculosis and another group of 216 without tuberculosis were included in the study.The sensitivity of Xpert for active tuberculosis was 62.78%,lower than that of IGRAs(P<0.05),and the specificity was 100%,higher than those of IGRAs and TST(both P<0.001).The sensitivity of Xpert was lower than that of IGRAs in the children younger than 5 years old(74.71%vs.67.47%,P>0.05),while the sensitivity of Xpert was significantly lower than that of IGRAs in the children older than 5 years old(58.26%vs.84.62%,P<0.001).The sensitivity of the pulmonary tuberculosis group was significantly higher than that of the extrapulmonary tuberculosis group(P<0.001).There were statistical differences among the different types of specimens(P<0.05),With the highest sensitivity of Xpert detected with bronchoalveolar lavage fluid(BALF).For the suspected pulmonary tuberculosis,the sensitivity of Xpert tested in the BALF was higher than that tested in the sputum(P=0.012).For the suspected pulmonary plus extrapulmonary tuberculosis,the sensitivity of Xpert tested in therespiratory specimens was higher than that tested in the non-respiratory specimens(P=0.004).Conclusion Xpert is effective in diagnosing childhood active tuberculosis,especially used in testing pulmonary tuberculosis and BALF of those suspected children younger than 5 years old.For pulmonary plus extrapulmonary tuberculosis,Xpert with respiratory tract specimens are first recommended.