Identification of Lung and Intestinal Microbiome and Host Susceptibility in Severe Pneumonia, a Prospective, Multicenter Cohort Study

The human lung and intestinal microbiota play an important role in human health. At present, the correlation between lung and intestinal microbiota in severe pneumonia patients and host susceptibility is limited to small sample, single center studies. Due to sample size limitations, the pathogenesis of severe pneumonia caused by many pathogens remains unclear. This study plans to construct sputum, alveolar lavage fluid, feces, and whole blood samples of severe pneumonia patients admitted to the ICU from 2023 to 2025, and collect clinical data from patients to identify changes in lung and intestinal microbiome, host susceptibility, and disease progression risk in different groups of patients.