Broad range detection of viral and bacterial pathogens in bronchoalveolar lavage fluid of children to identify the cause of lower respiratory tract infections

Heping Wang,Marien I De Jonge,Zhi Xu,Christa E Van Der Gaast-De Jongh,Xuehui He,Wenjian Wang,Yonghong Yang,Xiaonan Li,Ronald De Groot,Yuejie Zheng,Jiali Gu

doi:10.1186/s12879-021-05834-0

Abstract

BackgroundKnowledge on the etiology of LRTIs is essential for improvement of the clinical diagnosis and accurate treatment. Molecular detection methods were applied to identify a broad range of bacterial and viral pathogens in a large set of bronchial alveolar lavage (BAL) fluid samples. The patterns of detected pathogens were correlated to the clinical symptoms.MethodsBAL fluid samples and clinical data were collected from 573 hospitalized children between 1 month and 14 years of age with LRTIs, enrolled from January to December 2018. Pathogens were detected using standardized clinical diagnostics, with a sensitive, high-throughput GeXP-based multiplex PCR and with multiplex qPCR. Data were analyzed to describe the correlation between the severity of respiratory tract disease and the pathogens identified.ResultsThe pathogen detection rate with GeXP-based PCR and multiplex qPCR was significantly higher than by clinical routine diagnostics (76.09% VS 36.13%,χ2 = 8.191, P = 0.004). The most frequently detected pathogens in the BAL fluid were human adenovirus (HADV)(21.82%), Mycoplasma pneumoniae (20.24%), human rhinovirus (13.96%), Streptococcus pneumoniae (8.90%) and Haemophilus influenzae (8.90%). In 16.4% of the cases co-detection with two or three different pathogens was found. Viral detection rates declined with age, while atypical pathogen detection rates increased with age. Oxygen supply in the HADV and Influenza H1N1 infected patients was more frequent (49.43%) than in patients infected with other pathogens.ConclusionBroad range detection of viral and bacterial pathogens using molecular methods is a promising and implementable approach to improve clinical diagnosis and accurate treatment of LRTI in children.

Highlights

Knowledge on the etiology of Lower respiratory tract infections (LRTIs) is essential for improvement of the clinical diagnosis and accurate treatment
The etiology is complex as a whole range of different pathogens, mainly viruses and bacteria, in different combinations, can cause LRTI
The collection of bronchial alveolar lavage (BAL) fluid was done within the Department of Respiratory Diseases in Shenzhen Children’s Hospital for pathogen identification using standardized clinical diagnostic assays, as described here below, to facilitate the clinical decision for treatment

Summary

Introduction

Knowledge on the etiology of LRTIs is essential for improvement of the clinical diagnosis and accurate treatment. Lower respiratory tract infections (LRTI) are the leading cause of morbidity and mortality in children aged < 5 years worldwide [1]. The etiology is complex as a whole range of different pathogens, mainly viruses and bacteria, in different combinations, can cause LRTI. Accurate detection of respiratory tract pathogens is crucial for the clinical diagnosis and for the epidemiology of LRTIs [3]. Bronchoalveolar lavage (BAL) has been considered the gold standard for detection of the causative agents of lower respiratory tract infections. Large studies detecting both viral and bacterial pathogens are needed to better understand the cause-effect relation, the course of disease and the level of severity to improve treatment and accelerate the recovery from LRTI

Methods

Results

Conclusion