(1152) Prevotella Positivity in Airway May Be a Protective Factor for Pneumonia Patients

Introduction: Prevotella plays a key role in balancing health and many diseases. However, the distribution of Prevotella in the airway and its relationship with related diseases have been rarely explored. We explored the prognostic and predictive value of the Prevotella in pneumonia.

Methods: We retrospectively included 294 pneumonia patients treated at 8 institutes from March 2021 to November 2023. Clinical characteristics and experimental test data were collected from medical records at 24 hours after the pneumonia diagnosis, as well as their metagenomics next generation sequencing results. The study examined the association between Prevotella and the patients’ clinical characteristics and other microbial distributions and prognosis.

Results: The prevalence of Prevotella-positivity was 71.09% (209/294). Preliminary multivariate regression analysis showed that Prevotella-positivity may be a protective factor (HR 0.172; 95% CI 0.054-0.554; P = 0.003) and high international normalized ratio may be a risk factor (HR 2.329; 95% CI 1.269-4.276; P = 0.006). Further analysis showed that patients in the Prevotella-positive group and the Prevotella-negative group had significant statistical differences in in-hospital mortality (P < 0.001), invasive mechanical ventilation usage (P < 0.001) and incidence of severe pneumonia (P = 0.031). After comparative analysis of the basic characteristics and microbial distribution of the two groups, we found that the protective effect of Prevotella-positivity was more obvious in the low neutrophil to lymphocyte ratio group (HR 0.078; 95% CI 0.008-0.746; P = 0.027) and the male group (HR 0.054; 95% CI 0.012-0.237; P < 0.001) and the Streptococcus pneumoniae-positive group (HR 0.036; 95% CI 0.005-0.254; P < 0.001). Meanwhile, we found that the protective effect on overall survival was more pronounced when Prevotella reads was higher (HR 0.039; 95% CI 0.005-0.301; P = 0.002).

Conclusions: Prevotella-positivity is a protective factor for overall survival in pneumonia. Its protective effect may be influenced by basic characteristics such as sex and the distribution of microorganisms such as Streptococcus pneumoniae. The corresponding results need to be further verified in prospective studies with large sample sizes.