Exploring the microbiome difference in lower respiratory tract between community-acquired pneumonia with or without copd based on metagenomic sequencing: a retrospective study

SESSION TITLE: Chest Infections Posters 10 SESSION TYPE: Original Investigation Posters PRESENTED ON: 10/11/2023 12:00 pm - 12:45 pm PURPOSE: Pulmonary physicians may choose a different empirical antibiotic therapy when faced with a community-acquired pneumonia(CAP) patient concomitant with chronic obstructive pulmonary disease(COPD) compared to a CAP patient without COPD. However, the detailed microbiome distribution in lower respiratory tract of CAP with COPD or CAP without COPD was unknown. So we used metagenomic next generation sequencing(mNGS) to explore the microbiome differences between the two groups. METHODS: 36 CAP without COPD and 11 CAP with COPD cases were retrieved. Bronchoalveolar lavage fluid(BALF) was collected and analyzed using untargeted mNGS and bioinformatic analysis. RESULTS: mNGS revealed that at genus level, CAP with COPD group was abundant with Streptococcus, Prevotella, Bordetella, etc. While CAP without COPD group was abundant with Ralstonia, Prevotella, Streptococcus, etc. At species level, the top 10 of CAP with COPD group were Cutibacterium acnes, Rothia mucilaginosa, Bordetella genomosp. 6, etc. While the top 10 of CAP without COPD group were Ralstonia pickettii, Rothia mucilaginosa, Prevotella melaninogenica, etc. Meanwhile, both alpha and beta microbiome diversity was similar between groups. Linear discriminant analysis found that paraburkholderia, corynebacterium tuberculostearicum and staphylococcus hominis were more enriched in CAP without COPD group while the abundance of streptococcus intermedius,streptococcus constellatus,streptococcus milleri, fusarium was higher in CAP with COPD group. As microbiome diversity index, Simpson index was negatively correlated with age (R=-0.308, p= 0.0355) while ACE was positively correlated with number of eosinophils(R=0.3, p= 0.0403). CONCLUSIONS: These findings revealed that concomitant COPD had an impact on lower airway microbiome of CAP patients. CLINICAL IMPLICATIONS: This finding provides physician or pneumonologist with a detailed insight of lower airway microbiome of CAP patients with or without COPD and offer them more information when they are treating CAP patients and choosing different antibiotics. DISCLOSURES: No relevant relationships by Wei Li No relevant relationships by Min Tan No relevant relationships by Bingbing Wang No relevant relationships by Changhui Wang No relevant relationships by Shuanshuan Xie