Microbial Characterization of Patients with Community-Acquired Pneumonia by Targeted Next-Generation Sequencing Technology

Background: Community-acquired pneumonia (CAP) has a complex and regionally varying pathogen distribution, and traditional testing methods may underestimate mixed infections and difficult-to-cultivate pathogens. Objectives: In this study, we analyzed the microbial characteristics of bronchoalveolar lavage fluid (BALF) from CAP patients using targeted next-generation sequencing (tNGS) to provide a basis for optimizing pathogenic diagnosis and individualized treatment. Methods: A retrospective analysis was conducted on clinical data from 50 CAP patients admitted to Zibo First Hospital in 2024. Patient information collected included baseline characteristics, laboratory findings, and imaging data [Computed Tomography (CT)]. Chi-square analysis, Mann–Whitney U test, and stepwise regression were used to evaluate associations between clinical features and microbial characterization. Results: Among the 50 CAP patients, 15 (30%) were female and 35 (70%) were male. Klebsiella pneumoniae (n = 15), Epstein-Barr virus (EBV) (n = 14), and Candida albicans (n = 14) were among the most frequently detected microorganisms. Strong collinearity (R > 0.80, P < 0.05) was observed between the following microbial pairs: Proteus mirabilis and Serratia marcescens, enterovirus D68 and Streptococcus pneumoniae, Aspergillus versicolor and Moraxella catarrhalis, Haemophilus influenzae and S. intermedius. Female patients exhibited a significantly higher rate of Staphylococcus aureus infection compared to male patients (U = 192.50, z = -3.15, P = 0.002). Regression analysis indicated that patient age had a significant positive effect on the diversity of microbial infections (β = 0.052, t = 3.948, P < 0.001). Conclusions: Klebsiella pneumoniae, EBV, and C. albicans may play important roles in CAP. Older CAP patients are more likely to harbor a broader spectrum of viral and fungal pathogens, highlighting the need for heightened clinical attention in this population.