Comparative Genomic Analysis and Phenotypic Characterization of Bronchoscope-Associated Klebsiella Aerogenes

Abstract

Background: Bronchoscopes has been linked to the outbreaks of nosocomial infections. We aim to investigate the phenotypic and genomic profiles of bronchoscope-associated Klebsiella aerogenes isolates, and their association with genome public available isolates from human and environment.Methods: We performed a prospective single-center study sampling echoendoscopes after clinical use and after normal decontamination procedures. Bacterial screening was conducted by culturing the sample on Mueller-Hinton agar plates. Antimicrobial susceptibility testing was performed using the broth microdilution method. Whole-genome sequencing of K. aerogenes isolates was performed using an Illumina HiSeq system and comparative genomics analysis were conducted.Results: Over the 5-month period, a total of 358 isolates and 13 isolates were recovered from samples after clinical procedures and samples after decontamination procedures, respectively. Antimicrobial susceptibility testing found 7 K. aerogenes isolates to exhibit low-level resistance to antimicrobial agents. Among 7 K. aerogenes isolates, we found 5 sequence types (STs). Whole genome sequencing and comparison analysis observed the genetic diversity in our bacterial collection, which clustered into three main clades. Furthermore, we identified a total of 43 antimicrobial resistance genes in the K. aerogenes core genomes. As expected, human isolates encoded more antimicrobial resistance genes than that environmental isolates. Conclusions: This study first described the phenotypic and genomics characteristics of bronchoscope-associated K. aerogenes. The present observations demonstrated that broadly investigation of specific pathogens using publicly available global genomes offered the opportunity to identify prevalent clones associated with various hosts, sources, and geographical locations.