摘要目的 通过采用RNA恒温扩增(SAT)技术,对肺炎患儿的肺泡灌洗液标本进行检测,并结合体外培养实验,评估该技术检测活菌的能力,为SAT技术在肺炎支原体(MP)肺炎诊疗中的应用提供理论支持.方法 收集天津市儿童医院2015年10月至2017年12月临床确诊为社区获得性肺炎的572例患儿的肺泡灌洗液,利用MP核酸定量和SAT技术检测MP感染情况,并对161份肺泡灌洗液进行分离培养,培养阳性菌液中持续加入高浓度抗生素,同时进行MP核酸定量和SAT技术检测.结果 MP核酸定量和SAT技术的MP阳性检出率分别为74.7％(427/572)和71.9％(411/572),两种检测方法具有很高的一致性(χ2=1.142,P=0.285).根据SAT技术的检测结果,572例肺炎患儿中男性患儿阳性率为72.7％(224/308),女性患儿阳性率为70.8％(187/264),不同性别患儿阳性率差异无统计学意义(χ2=0.252,P=0.616).不同年龄患儿MP检出阳性率不同,婴幼儿(≤3岁)阳性率为56.6％(94/166),学龄前期和学龄期儿童(4～14岁)阳性率为78.1％(317/406),学龄前期和学龄期儿童的阳性率明显高于婴幼儿,差异有统计学意义(χ2=26.811,P=0.000).通过SAT技术检测活菌的能力的实验发现,MP阳性培养液中连续5 d加入5 MIC阿奇霉素后,MP核酸定量检测阳性,SAT技术检测则为阴性.结论 SAT技术具有高灵敏度和高特异性,并且可以鉴别"死菌""活菌",可以快速准确检测MP感染情况,并能有效评估临床治疗效果.

abstractsObjective To assess the ability of simultaneous amplification and testing ( SAT ) in bacteria detection , bronchoalveolar lavage fluid from children was collected and detected by SAT , combined with in vitro culture experiment , providing theoretical support for the application of SAT in the diagnosis and treatment of mycoplasma pneumonia ( MP ) .Methods A total of 572 bronchoalveolar lavage fluid from children with community acquired pneumonia during October 2015 and December 2017 in Tianjin Children′s Hospital were collected and detected by Mycoplasma pneumonia ( MP ) nucleic acid quantitative assay and SAT technology.Among them, 161 bronchoalveolar lavage fluid were also detected using in vitro culture and the positive ones for MP were analyzed by nucleic acid quantification and SAT after exposing to high concentration of antibiotic .Results The positive rates of MP by nucleic acid quantitative assay and SAT technology in 572 samples were 74.7％ (427/572) and 71.9％ (411/572), respectively.These two detection methods have high consistency (χ2 =1.142,P=0.285).According to the test results of SAT , the positive rates of male and female were 72.7％(224/308) and 70.8％(187/264), respectively.There was no significant difference of positive rate between different sex (χ2 =0.252, P=0.616).The positive rate of MP in 4-14 years old children (78.1％, 317/416) was higher than that in infants (≤3 years) (56.6％, 94/166) (χ2 =26.811, P=0.000).After adding azithromycin (5 MIC) to MP positive medium for 5 days, the result of nucleic acid quantification was positive but SAT was negative .Conclusions SAT technology is a rapid, sensitive and specific method for detection of MP .In addition, SAT technology could identify the "dead" and"live" bacteria and could evaluate the effect of clinical treatment effectively .