Gut Microbiome Dysfunction in Sepsis and Trauma Survivors

Study Overview
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Brief Summary
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Gastrointestinal microbiome dysfunction has been demonstrated to be a culprit of various systemic dysfunctions in peripheries such as cardiovascular, nervous, endocrine and musculoskeletal systems. The topic of microbiome dysfunction after sepsis and trauma injury is understudied but may be responsible for persistent systemic inflammation clinically observed in sepsis and trauma survivors. Therefore, the objective of this project is to investigate the gut microbiome after acute phase of sepsis or severe trauma injury and compare it with 108 age-matched healthy population controls

Detailed Description
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The investigators hypothesize that alterations of the gut microbiota will correlate with persistent systemic inflammation in sepsis and trauma survivors compared to existing healthy population controls. This research group will collect stool samples from 108 sepsis survivors and 108 trauma survivors (groups of ages 18-45, 46-64, and >65; male and female; n=18 per age + sex cohort) admitted to the surgical intensive care unit between day 7 and 28 of hospital admission, as well as 3 and 6 months after their sepsis or trauma event. The investigators will perform 16S rRNA DNA sequencing on the isolated bacterial DNA from these samples and bioinformatic analysis to determine microbiota alterations between time points and between sepsis and control cohorts. In addition, the investigators will draw 20ml of blood to isolate plasma. Trauma Subgroup for traumatic brain injury (TBI) pilot study: Our team will enroll 15 additional trauma injury patients with traumatic brain injury. This subgroup will have an added stool (if available) and blood sample collection after initial injury (+ 5 days). The additional sample will be compared to the sample collected at 14-21 days and follow up samples at 3 and 6 months. The results will be associated with Glasgow Outcome Scale Extended at 3 and 12 month time points and the recorded discharge Rancho Los Amigos scale score from the medical record. The specific aims will be: Aim 1 - define the impact of persistent systemic inflammation on the gastrointestinal microbiota in sepsis and trauma survivors and Aim 2 - identify microbial genes associated with persistent systemic inflammation in sepsis and trauma survivors compared to normal controls. Trauma Subgroup Aim: Pilot study to test the hypothesis that changes in the microbiome towards pathogenic microbe is associated with worsened outcomes in trauma injury patients with TBI (traumatic brain injury).

Official Title
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Gut Microbiome Dysfunction in Sepsis and Trauma Survivors

Conditions
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Sepsis, Trauma Injury

Intervention / Treatment
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* Other: Human feces collection


Participation Criteria
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Eligibility Criteria
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Sepsis Population Inclusion Criteria Admission to the 46, 77, 87, 4 East, 4 West, or 24-5 ICUs where clinical care can be managed by the critical care organization guided by standard operating procedures. Age ≥18 years Meets Sepsis 3 criteria at time of sepsis diagnosis Has remained in ICU for 14 days (+/- 7 days) following sepsis diagnosis. Ability to obtain patient/LAR informed consent. Is receiving adequate nutritional intake: oral or enteral nutrition. Exclusion Criteria Severe traumatic brain injury with unencumbered assessment of GCS equaling 3 on admission to intensive care unit Refractory shock (i.e., patients who are expected to die within 12 hours). Uncontrollable source of sepsis (e.g. irreversible disease state such as unresectable dead bowel). Patient or patient's family are not committed to aggressive management of the patient's condition. Known HIV infection with CD4 count <200 cells/mm3. Organ transplant recipient on immunosuppressive agents. Known pregnancy. Prisoners. Institutionalized patients j Inability to obtain informed consent. k) Burn injury greater than 20% TBSA (total body surface area) Trauma Population Inclusion Criteria 1. All adults (age ≥18 to 54) require both: a. Blunt and/or penetrating trauma patient with i. Hemorrhagic shock defined by: 1. Systolic BP (SBP) ≤ 90 mmHg or 2. Mean arterial pressure ≤ 65 mmHg or 3. Base deficit (BD) ≥5 meq or 4. Lactate ≥ 2 or 5. Active red blood cell or whole blood transfusion within 6 hours of arrival b. Injury Severity Score (ISS) greater than or equal to 15 2. All adults (age 55 and older) require: a. Either hemorrhagic shock defined by: i. Systolic BP (SBP) ≤ 90 mmHg or ii. Mean arterial pressure ≤ 65 mmHg or iii. Base deficit (BD) ≥5 meq or iv. Lactate ≥ 2 or v. Active red blood cell or whole blood transfusion within 6 hours of arrival OR b. Injury Severity Score (ISS) greater than or equal to 15. 3. Ability to obtain Informed Consent Exclusion Criteria Patients not expected to survive greater than 48 hours. Prisoners. Pregnancy. Previous bone marrow transplantation. Patients with End Stage Renal Disease. Patients with any pre-existing hematological disease (e.g. hemochromatosis, myelodysplastic syndrome, hematologic cancers) Burn injury greater than 20% TBSA Severe traumatic brain injury with unencumbered assessment of GCS equaling 3 on admission to intensive care unit. Trauma TBI subgroup (15 participants) Inclusion criteria will be: 1. Any adult age 18 or older with any traumatic bleed (intracerebral hemorrhage, subarachnoid hemorrhage, intraparenchymal hemorrhage, subdural hematoma, cerebral epidural hematoma) and any GCS (Glasgow Coma Score). Exclusion criteria is the same used for the trauma cohort. Healthy Control Inclusion criteria will be: All adults (age ≥18) Ability to obtain Informed Consent prior to blood collection. Exclusion Criteria will be: Current, chronic steroid use Pregnancy Current or recent (within 7 days) use of antibiotics.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 110 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 |
| --- | --- |
| Sepsis Survivors<br>Feces collected between 7 to 28 days of hospital admission and at 3 and 6 months post hospitalization. Telephone call at 12 months. Blood will be collected at time of first feces collection | Other: Human feces collection<br>* Human feces collection and blood sampling<br>* Other names: Blood sampling;|
| Healthy Control Population<br>One time collection of feces and blood upon enrollment used for comparison to identify microbial genes associated with persistent systemic inflammation in sepsis survivors. | Other: Human feces collection<br>* Human feces collection and blood sampling<br>* Other names: Blood sampling;|
| Trauma Survivor<br>Feces collected between 7 to 28 days of hospital admission and at 3 and 6 months post hospitalization. Telephone call at 12 months. Blood will be collected at time of first feces collection | Other: Human feces collection<br>* Human feces collection and blood sampling<br>* Other names: Blood sampling;|
| Traumatic Brain Injury (TBI)<br>Feces collected at admission (day 1(+5)) and between 7 to 28 days of hospital admission and at 3 and 6 months post hospitalization. Telephone call at 12 months. Blood will be collected at time of first and second feces collection. | Other: Human feces collection<br>* Human feces collection and blood sampling<br>* Other names: Blood sampling;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Determine the impact of persistent systemic inflammation on gastrointestinal microbiota in sepsis and trauma survivors & identify microbial genes associated with persistent systemic inflammation of sepsis & trauma survivors compared to normal controls. | Identify gut microbiome dysfunction through Microbial Taxonomic Analysis and Meta-transcriptomic Analysis | through study completion, an average of 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Sepsis; Trauma; Microbiome