[Screening and antibiotic resistance analysis of nasal colonized bacteria in patients with chronic rhinosinusitis]

Objective:Since bacterial infection is one of the common pathogenic factors lead to chronic rhinosinusitis （CRS）, our study is designed to investigate the prevalence and antibiotic resistance of nasal colonized bacteria in patients with CRS, and to analyze the correlation between nasal colonized bacteria and pathogenesis of CRS. Method:Nasal vestibule samples collected from 200 patients with CRS were automatically inoculated on to various bacterial culture medium, cultured by WaspLab microbiology automated system, potential pathogenic bacterial colonies grew on agar plates were then examined, identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry, and analyzed their antibiotic-resistant phenotype by antibiotic susceptibility testing. Result:Two hundred and seventy-five bacterial strains of nasal colonization were isolated, including coagulase-negative Staphylococci, Staphylococcus aureus, Streptococcus pneumonia, Moraxella catarrhalis, Haemophilus influenza, Pseudomonas aeruginosa, and Enterobacteriaceae such as Escherichia coli and Klebsiella pneumoniae. All strains displayed various degrees of antimicrobial resistance among children and adult patients, or among patients with and without endoscopic sinus surgery. Conclusion:The constitution of nasal colonized commensal bacteria in patients with CRS was partially similar to that of pathogenic bacteria causing CRS. They may form a reservoir of antimicrobial resistant pathogens, which would transform into pathogenic bacteria causing CRS under certain conditions. Screening of nasal colonized bacteria may represent an alternative approach for diagnosis and treatment of CRS.