Microbiome and Host Susceptibility in Severe Pneumonia, a Prospective, Multicenter, Cohort Study

Study Overview
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Brief Summary
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This study was a prospective multicenter cohort of severe pneumonia. And by collecting clinical samples to clarify the correlation between lung microbiome, intestinal microbiome, host susceptibility, and prognosis of severe pneumonia patients.

Detailed Description
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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.

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

Conditions
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Severe Pneumonia

Intervention / Treatment
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* Diagnostic Test: metagenomics


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. New lung infection that meets one of the following definitions: the patient receives mechanical ventilation (invasive or non-invasive) due to acute respiratory failure, with a PEEP level of 5cm or above; Patients receiving high flow oxygen therapy with a FiO2 of 50% or more and a PaO2: FiO2 ratio below 300 Exclusion Criteria: Expected length of stay in ICU is less than 1 day Pregnant

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Severe pneumonia<br>Definition of severe pneumonia: New infection that meets one of the following definitions: the patient receives mechanical ventilation (invasive or non-invasive) due to acute respiratory failure, with a PEEP level of 5cm or above; The patient receives high flow oxygen therapy with a FiO2 of 50% or more and a PaO2: FiO2 ratio of less than 300; The patient receives oxygen treatment with a partial respiration mask with an air storage bag, provided that PaO2 is lower than the pre-specified indicator. | Diagnostic Test: metagenomics<br>* Perform metagenomic analysis on balf, feces, and blood<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The correlation between lung microbiome and disease prognosis | 1. Identification of microbial gene profiles; 2. Analysis of host health dynamics and trends; 3. Identification of host gene mutations; 4. Preliminary model construction; 5. Model optimization and evaluation. | 60 days |