Pathobiomes in Gut of Critically Ill Patients

NCT ID: NCT06822465

Last Updated: 2026-02-02

Basic Information

• Recruitment Status: RECRUITING
• Total Enrollment: 100 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2024-12-19
• Study Completion Date: 2029-12-31

Brief Summary

Despite powerful antibiotics, 50% of the intestinal tracts of critically ill surgical patients are colonized by Pseudomonas aeruginosa, whose mere presence in this site increases mortality fourfold by mechanisms that remain unknown. Many patients who survive the initial surgical trauma still succumb to multi-organ failure and septicemia secondary to an invasive nosocomial infection. The sequelae of shock, hypoxia, and parental nutrition result in injury to the intestinal mucosa, changes in gut permeability, and failure of intestinal defense mechanisms. These conditions put patients at risk for infection and multiple organ failure secondary to the translocation of enteric bacteria, initiating a systemic release of inflammatory mediators-a process that has been termed gut-derived sepsis.

Intestinal P. aeruginosa senses host factors released during stress and responds by activating its virulence gene machinery. As such, the presence of a highly activating intestinal milieu serves to induce virulence in strains of P. aeruginosa and this correlates to the severity of a patient's illness. While the host-pathogen interaction is a dynamic process, the study expects that as a patient's illness worsens or resolves over time, the "virulence-activating" properties of their intestinal milieu will change accordingly. This study will conduct a prospective observational trial in a population of critically ill patients at the Universtiy of Chicago Medical Center. This trial will entail collecting and screening stool samples obtained from critically ill patients for their virulence inducing capabilities on laboratory strains of P. aeruginosa using in vitro and in vivo assays. The study also plans to isolate strains of intestinal P. aeruginosa from stool samples to determine the prevalence of intestinal P. aeruginosa in a population of critically ill patients.

Conditions

Pseudomonas Aeruginosa

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

Critically Ill Patients

All patients admitted to the burn intensive care unit (BICU), surgical intensive care unit (SICU), and the medical intensive care unit (MICU) longer than 24 hours at University of Chicago Medical Center

P. aeruginosa using in vitro and in vivo assays

Intervention Type: OTHER

This trial will entail collecting and screening stool samples obtained from critically ill patients for their virulence inducing capabilities on laboratory strains of P. aeruginosa using in vitro and in vivo assays. The investigators also plan to isolate strains of intestinal P. aeruginosa from stool samples to determine the prevalence of intestinal P. aeruginosa in a population of critically ill patients.

Interventions

P. aeruginosa using in vitro and in vivo assays

This trial will entail collecting and screening stool samples obtained from critically ill patients for their virulence inducing capabilities on laboratory strains of P. aeruginosa using in vitro and in vivo assays. The investigators also plan to isolate strains of intestinal P. aeruginosa from stool samples to determine the prevalence of intestinal P. aeruginosa in a population of critically ill patients.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Any ethnicity
• Age > 18 years and < 85 years

Exclusion Criteria

• A known history of HIV/AIDS
• Active pregnancy
• Are incarcerated will be excluded from the study.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 85 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

National Institutes of Health (NIH)

NIH

Sponsor Role: collaborator

National Institute of General Medical Sciences (NIGMS)

NIH

Sponsor Role: collaborator

University of Chicago

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

John Alverdy, MD FACS FSIS

Role: PRINCIPAL_INVESTIGATOR

University of Chicago

Locations

The University of Chicago

Hyde Park, Illinois, United States

Site Status: RECRUITING

Countries

United States

Central Contacts

John Alverdy, MD FACS FSIS

Role: CONTACT

jalverdy@bsd.uchicago.edu

773-702-4876

Leila Yazdanbakhsh, MSCI

Role: CONTACT

leila.yazdanbakhsh@bsd.uchicago.edu

773-834-5087

Facility Contacts

John Alverdy, MD FACS FSIS

Role: primary

773-834-5087

Leila Yazdanbakhsh, MD FACS FSIS

Role: backup

leila.yazdanbakhsh@bsd.uchicago.edu

7738345087

Other Identifiers

5R01GM062344-23

Identifier Type: NIH

Identifier Source: secondary_id

View Link

16494B

Identifier Type: -

Identifier Source: org_study_id