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Updated: Jun 23, 2026
04:32
Murine Oropharyngeal Aspiration Model of Ventilator-associated and Hospital-acquired Bacterial Pneumonia
Published on: June 28, 2018
Spatio-temporal differences and associations between upper and lower respiratory microbiota in ventilator-associated
Hong Yang1, Xin-Xin Ni2, Feng Xu1
1Wuxi Maternal and Child Health Hospital, Wuxi School of Medicine, Jiangnan University, Jiangsu, China.
Frontiers in Cellular and Infection Microbiology
|June 22, 2026
Summary
This study reveals dynamic changes in respiratory microbiota during ventilator-associated pneumonia (VAP) progression. Key bacteria like Prevotella and Leptotrichia show potential as early diagnostic biomarkers for VAP.
Area of Science:
- Microbiology
- Critical Care Medicine
- Genomics
Background:
- Ventilator-associated pneumonia (VAP) is a significant cause of death in critically ill patients on mechanical ventilation.
- Understanding the microbial dynamics in the respiratory tract is crucial for VAP management.
Purpose of the Study:
- To explore spatiotemporal changes in upper (URT) and lower respiratory tract (LRT) microbiota during VAP.
- To identify early diagnostic biomarkers for VAP and understand its pathophysiology.
Main Methods:
- Analyzed 16S rRNA gene sequencing data from 123 samples.
- Used DADA2 for data processing and Silva 138 database for taxonomy assignment.
- Employed diversity metrics and LEfSe analysis to identify key bacterial genera, with ROC analysis for diagnostic potential.
Main Results:
- Increased URT alpha diversity in VAP groups; distinct microbial structures in URT and LRT across disease stages.
- Identified Prevotella, Leptotrichia, and Peptostreptococcus as potential early diagnostic biomarkers.
- Observed synchronized microbial translocation from URT to LRT by day 7 post-intubation.
Conclusions:
- Dynamic respiratory microbiota changes occur during VAP progression.
- Identified potential microbial biomarkers for early VAP detection and intervention.
- Highlights the need for monitoring URT-LRT microbial interactions for proactive VAP management.
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