肺泡灌洗液宏基因二代测序在儿童重症肺炎病原诊断中的价值

Value of metagenomics next-generation sequencing in bronchoalveolar lavage fluid in the etiological diagnosis of children with severe pneumonia

目的探讨肺泡灌洗液(BALF)宏基因二代测序(mNGS)对儿童重症肺炎病原的诊断价值。方法选取2019年6月至2020年12月于西安市儿童医院住院诊断为重症肺炎的146患儿的BALF进行传统实验室检测(常规培养+涂片)和mNGS检测。分析BALF mNGS检测与常规培养+涂片检测对病原微生物的检出结果。结果BALF mNGS检测病原阳性率为80.1%(117/146),前3位依次为肺炎链球菌55株、肺炎支原体43株、流感嗜血杆菌18株。常规培养+涂片检测病原阳性率为18.5%(27/146),前3位分别为肺炎链球菌6株、流感嗜血杆菌4株、肺炎支原体4株。单一感染最多的是肺炎链球菌,混合感染最多的是肺炎支原体+肺炎链球菌。BALF mNGS检测病原阳性率高于常规培养+涂片检测(χ^(2)=84.65,P<0.05)。血清肺炎支原体抗体检测病原阳性率为39.7%(58/146),BALF mNGS检测病原阳性率为29.5%(43/146),差异具有统计学意义(χ^(2)=78.76,P<0.05)。结论BALF mNGS检测对儿童重症肺炎病原的检出率高于常规培养+涂片检测,可在早期指导临床合理用药。

Objective To investigate the value of metagenomics next-generation sequencing(mNGS)in bronchoalveolar lavage fluid(BALF)in the etiological diagnosis of children with severe pneumonia.Methods The BALF of 146 children diagnosed with severe pneumonia hospitalized in Xi’an Children’s Hospital from June 2019 to December 2020 were selected and detected by traditional laboratory tests(routine culture+smear)and mNGS.The results of BALF mNGS detection and routine culture+smear detection for pathogenic microorganisms were analyzed.Results The positive rate of pathogen detected by BALF m NGS was 80.1%(117/146),and the top three were 55 strains of Streptococcus pneumoniae,43strains of Mycoplasma pneumoniae,and 18 strains of Haemophilus influenzae.The positive rate of pathogen detected by routine culture+smear was 18.5%(27/146),and the top three were 6 strains of Sreptococcus pneumoniae,4 strains of Haemophilus influenzae and 4 strains of Mycoplasma pneumoniae.Streptococcus pneumoniae is the most common single infection,and Mycoplasma pneumoniae+Streptococcus pneumoniae is the most common mixed infection.The positive rate of pathogen detected by BALF mNGS was higher than that detected by routine culture+smear(χ^(2)=84.65,P<0.05).The positive rate of Mycoplasma pneumoniae antibody in serum was 39.7%(58/146),that of BALF mNGS was 29.5%(43/146),and the difference was statistically significant(χ^(2)=78.756,P<0.05).Conclusion The etiological detection rate of BALF mNGS in children with severe pneumonia is higher than that of routine culture+smear detection,which can guide clinical rational drug use in the early stage.