Discover the Immune Signature of Sepsis Caused by Acute Pulmonary Infection: A Cohort Study

Study Overview
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Brief Summary
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The goal of this observational study is to describe the immune signature of acute pulmonary infection.The main questions it aims to answer are: Nasal mucosal immune response in patients with influenza infection Difference of immune response between Viral sepsis and Bacterial sepsis Immunological differences between Viral sepsis and Viral pneumonia

Detailed Description
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Aging could influence host immune response. Elderly people are more likely to progress to severe pneumonia than young people. Nasal mucosa is the initial infection site of influenza infection. Single cell sequencing of nasal mucosal cell that may provide valuable insights into host response to influenza infection. Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. Although bacteria are considered as the main pathgens of sepsis，SARS-CoV-2 or influenza infection also can cause multiple organ dysfunction which meet the definition of Sepsis 3.0. Viral sepsis has not received enough attention for a long time. It is important to understand the difference between viral sepsis and bacterial sepsis that may help to develop better strategies to diagnose and treat sepsis. Viral pneumonia is one of the leading infectious cause of death woldwide.Pneumina is the most common cause of sepsis.The mechanism of viral pneumonia progressing to sepsis needs to be further investigated.

Official Title
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Discover the Immune Signature of Sepsis Caused by Acute Pulmonary Infection: A Cohort Study

Conditions
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Sepsis, Viral Pneumonia, Influenza, Upper Respiratory Tract Infection

Intervention / Treatment
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* Other: pathogen


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥18 years at time of signing Informed Consent Form chest imaging confirmed pneumonia. Informed consent is obtained The pneumonia onset ≤8 days Exclusion Criteria: SaO2/SPO2≤94% on room air or Pa02/Fi02 ratio <300mgHg before the onset of pneumonia Severe liver disease (e.g. Child Pugh score ≥ C, AST>5 times upper limit) Patients with known severe renal impairment (estimated glomerular filtration rate ≤30 mL/min/1.73 m2) or receiving continuous renal replacement therapy, hemodialysis,peritoneal dialysis） Pregnant Or Lactating Women Patients were eligible for organ transplantation or had undergone previous organ transplantation surgery HIV infection Had unstable angina or myocardial infarction within 30 days without vascular recanalization treatment

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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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Influenza upper respiratory infection<br>This cohort aims to descirbe the nasal mucosal immune response in influenza patients. We will collect nasal mucosal cells from influenza patients using Nasal Cytology Curettes. Blood samples will also be obtained from the patient. All samples will be used for single cell sequencing. | Other: pathogen<br>* The patients were divided into groups according to the pathogen(bacteria or virus). The influenza upper respiratory tract infection cohort will be grouped mainly according to age.<br>* Other names: age;|
| Viral Sepsis and Viral pneumonia<br>The purpose of this cohort is to characterize the immune pattern of patients with viral sepsis and find specific target for the treatment of viral sepsis. Blood samples will be obtained from the viral sepsis/pneumonia patients.All samples will be used for transcriptome sequencing. | Other: pathogen<br>* The patients were divided into groups according to the pathogen(bacteria or virus). The influenza upper respiratory tract infection cohort will be grouped mainly according to age.<br>* Other names: age;|
| Bacterial Sepsis and Bacterial pneumonia<br>This cohort served as a control for the viral sepsis/pneumonia cohort.Blood samples will be obtained from the bacterial sepsis/pneumonia patients.All samples will be used for transcriptome sequencing. | Other: pathogen<br>* The patients were divided into groups according to the pathogen(bacteria or virus). The influenza upper respiratory tract infection cohort will be grouped mainly according to age.<br>* Other names: age;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| upper respiratory infection or pneumonia or Sepsis | Patients were grouped and compared according to their diagnosis. | up to 28 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical status | assessed by Sequential Organ Failure Assessment | days 0, 3, 7 | 
| All cause mortality |  | up to 28 days | 
| Length of hospital stay (days) |  | up to 28 days | 
| Length of ICU stay (days) |  | up to 28 days |