농흉 환자의 흉강 및 구강 내 미생물 군집 분석 및 메타유전체 연구

Abstract

Background: Several studies have suggested that the oral microbiome is associated with various diseases. Although epidemiological studies on the oral microbiome in infectious diseases are increasing, no systemic studies exist on the oral microbiome of patients with pleural empyema. In this study, we present the microbiome characteristics of patients with pleural empyema and controls based on 16S ribosomal RNA gene sequencing. Methods: Twenty individuals–10 with pleural empyema and 10 in the control group–were recruited for this study. Specimens of the oral cavity (saliva, gingival tissue, tongue, and buccal mucosa) and pleural fluid were collected from all participants. Oral and pleural microbiomes were analyzed using the Illumina MiSeq system, and the obtained sequence data were further analyzed using bioinformatics methods. The medical records of the enrolled patients were retrospectively reviewed. Results: No significant differences were observed in alpha and beta diversities among the oral sample sites. We found a high abundance of Acinetobacter, Staphylococcus, and Enterococcus in the oral mucosa and saliva of patients with empyema. Our results showed significantly low alpha diversity and microbial dysbiosis in patients with empyema (Shannon index, 1.8 ± 1.1 vs. 2.8 ± 0.6, p < 0.001). Likewise, beta-diversity analysis revealed significant differences in the composition of microbiomes between the empyema and control groups (p < 0.001). In addition, the alpha diversity of the pleural microbiome of patients with empyema was lower than that of controls in terms of both diversity (Shannon index, 1.2 ± 1.1 vs. 3.6 ± 0.4, p < 0.001) and richness (Chao1 index, 49.2 ± 22.2 vs. 199.7 ± 98.4, p = 0.001). Principal coordinate analysis indicated a significant difference in the pleural microbiome between empyema and control groups. Linear discriminant analysis of the functional potential of the oral microbiome demonstrated that two- component systems, amino acid metabolism, xenobiotic biodegradation, and metabolic pathways were overrepresented in patients with empyema relative to those in controls. Conclusion: This is the first study to explore the relationship between the oral microbiome and pleural empyema. This demonstrates that the oral microbiome harbors unique bacterial communities and identifies potential taxonomic and functional biomarkers in patients with empyema. Further investigation of the potential mechanism of population dynamics in the oral microbiome during the progression of pleural empyema is required. Keywords: Bacteria, Empyema, Pleural infection, Microbiota, Oral Health.