宏基因组二代测序在重症肺炎肺泡灌洗液中的检测优势

Advantages in pathogen detection of bronchoalveolar lavage fluid by metagenomic next‑generation sequencing in severe pneumonia

目的:探讨宏基因组二代测序(mNGS)在重症肺炎肺泡灌洗液中的检测优势。方法:选取2019年12月至2021年10月在武汉大学中南医院收治的70例重症肺炎患者,所有患者均已行mNGS和传统培养(肺泡灌洗液培养、痰培养),回顾性分析mNGS在重症肺炎患者中病原体检测的优势。结果:mNGS病原体检测的阳性率高于传统培养(98.6%vs 62.9%,P<0.001)。在传统培养阴性而mNGS阳性的患者中,mNGS能进一步识别出多种病原体感染。在病原体分布上,mNGS检出细菌71株、真菌39株和病毒3株。在混合感染中,mNGS诊断阳性率更高(67.1%vs 12.9%,P<0.001)。此外,在合并基础疾病的患者中,mNGS有更高的病原体检出率(98.0%vs 69.4%,P<0.001),尤其在合并免疫低下的患者中,mNGS可识别出特殊病原体(肺孢子菌、巨细胞病毒)感染。结论:mNGS可以提高重症肺炎患者病原微生物的检出率,可作为传统培养阴性的重症肺炎患者的补充检测技术。mNGS在混合感染诊断中有优势,能同时识别多种病原体感染。临床上,推荐合并免疫缺陷的重症肺炎患者尽早应用mNGS,增加临床获益。

Objective:To investigate the advantages of metagenomic next-generation sequencing(mNGS)in bronchoalveolar lavage fluid of severe pneumonia.Methods:From December 2019 to October 2021,70 patients with severe pneumonia at Zhongnan Hospital of Wuhan University were selected.All patients underwent the pathogen detections by mNGS and traditional culture(bronchoalveolar lavage fluid and sputum cultures).The advantages of bronchoalveolar lavage fluid pathogen detection by mNGS in severe pneumonia were retrospectively evaluated.Results:The positive rate of mNGS was higher than that of culture(98.6%vs 62.9%,P<0.001).mNGS further identified multiple-pathogen infections in patients with traditional culture-negative but mNGS positive.In terms of patho-gens distribution,mNGS detected 71 bacteria,39 fungi,and 3 viruses.In mixed infections,the positive rate of mNGS was higher(67.1%vs 12.9%,P<0.001).In addition,mNGS had a higher pathogen detection rate in patients with underlying diseases(98.0%vs 69.4%,P<0.001).Especially in immunocompromised patients,mNGS could recognize specific pathogens infection(such as pneumocystis and cytomegalovirus).Conclusion:mNGS can improve the detection rate of pathogenic microorganism in patients with severe pneumonia,which can be used as a complementary detection technique for patients with severe pneumonia who are negative in traditional culture.mNGS has advantages in diagnosing mixed infections and can simultaneously identify multiple pathogen infections.Clinically,mNGS is recommended for patients with severe pneumonia complicated with immunocompromise as soon as possible to increase clinical benefits.