Application Value of Metagenomic Next-generation Sequencing of Patho-gens in Bronchoalveolar Lavage Fluid for the Diagnosis of Lower Respira-tory Tract Infection

DONG Jian; LI Zhenzhen; LIU Zixiao

doi:10.3969/j.issn.1002-3429.2024.20.012

Abstract：Objective To explore the application value of metagenomic next-generation sequencing(mNGS)of pathogens in bronchoalveolar lavage fluid(BALF)for the diagnosis of lower respiratory tract infection(LRTIs),in order to improve the accuracy of pathogen detection of LRTIs and avoid delayed treatment.Methods A total of 115 patients with LRTIs admitted from January 2019 to December 2021 were selected,and BALF was collected,all of which were cultured by mNGS and traditional methods.The time of pathogen detection and the distribution of detected pathogens were compared and analyzed between mNGS and traditional methods,and the consistency of detection results between mNGS and traditional meth-ods was analyzed.The clinical data of mNGS-positive and negative patients were compared,and multivariate logistic regression was performed to analyze the factors affecting the results of mNGS testing.Results The detection time of pathogens by mNGS was significantly shorter than that by traditional methods(P＜0.05).The positive rate of pathogen detection by mNGS was 74.78%,which was higher than that by traditional methods(36.52%)(P＜0.01),and the positive detection rate of bacte-rial strains by mNGS was higher than that by traditional methods(P＜0.05,P＜0.01).The Kappa index of consistency be-tween mNGS detection and traditional detection method was 0.295,and there were significant differences in antibiotic use,glucocorticoid or immunosuppressant use,white blood cell(WBC)count,and C reactive protein(CRP)between mNGS-posi-tive and negative patients(P＜0.05,P＜0.01).Multivariate logistic regression analysis showed that antibiotics use,glu-cocorticoid or immunosuppressant use,WBC,and CRP had no effect on the results of mNGS detection(P＞0.05).Conclu-sion mNGS can significantly improve the accuracy of pathogen detection in LRTIs,provide a basis for precise antibiotic treat-ment,and avoid delayed treatment.