From Commensalism to Pathogenicity: Exploring the Pathophysiology of Bacteremia to Better Understand Enterococcus Faecalis Infective Endocarditis (BAC-ENDO)

January 7, 2026 updated by: University Hospital, Clermont-Ferrand

From Commensalism to Pathogenicity: Exploring the Pathophysiology of Bacteremia to Better Understand Enterococcus Faecalis Infective Endocarditisléter

Enterococci are pathobionts of the human intestinal microbiota: they colonize the gastrointestinal tract as well as the skin, urine, wounds, bile, the oral cavity and endodontic canal, and medical devices (urinary catheters, venous catheters, etc.). They are responsible for urinary, dental, bloodstream, endocardial, biliary, and gastrointestinal infections.

Enterococcus faecalis is the enterococcus most frequently isolated from clinical specimens. It is the third leading cause of infective endocarditis (infection of the cardiac valves) and the leading cause of endocarditis following TAVI (transcatheter aortic valve implantation via the femoral route). E. faecalis infective endocarditis (EFIE) is severe and difficult to treat, with a particularly high relapse rate despite appropriate antibiotic therapy.

Cardiac valve contamination is always secondary to E. faecalis bacteremia, particularly in cases of isolated E. faecalis bacteremia (EFIB), defined by the absence of an identifiable portal of entry. Once in the bloodstream, the bacterium adheres to the valvular endothelium (healthy or damaged) through specific virulence factors, including endocarditis- and biofilm-associated pili (ebp), the collagen adhesin Ace, and aggregation substance (Agg).

The classical portals of entry for EFIE are infections of the urinary tract and the gastrointestinal tract. However, despite extensive investigations, the source of infection remains unidentified in more than 50% of cases. An imbalance of the intestinal microbiota, leading to overgrowth and subsequent translocation of E. faecalis from the digestive tract into the bloodstream, could explain the absence of an identifiable portal of entry during routine clinical and paraclinical evaluations. This plausible hypothesis remains largely unexplored to date. A better understanding of the underlying pathophysiology-particularly gut dysbiosis and the pathogen's capacity for intestinal translocation-could improve the prevention of EFIE occurrence and relapse.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

90

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Patients aged 18 years and older;
  • Capable of giving informed consent;
  • Affiliated with a social security system;
  • Hospitalized with at least one positive blood culture for Enterococcus faecalis, without an obvious clinical entry point after physical examination and initial routine investigations (BIEF group);
  • Hospitalized for another bacteremia, without an obvious clinical entry point after initial routine investigations (Control group);
  • Receiving antibiotic therapy that was started less than 48 hours ago

Exclusion Criteria:

  • Refusal to participate in the study;
  • Pregnant or breastfeeding women;
  • Individuals under guardianship, curatorship, deprived of liberty, or under judicial protection;
  • Antibiotic therapy for the current infectious episode started more than 48 hours prior to inclusion.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Non-Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Other: Cases
Collection of four swabs (two rectal swabs, one oral swab, and one skin swab from the inguinal fold).
Biological: Microbiological sampling (swab collection)

Participants in the case group will undergo microbiological sampling consisting of four swabs: two rectal swabs, one oral swab, and one skin swab from the inguinal fold.

Participants in the control group will undergo a single rectal swab. The samples will be collected for microbiological analysis.
Other: Controls
Collection of a single rectal swab.
Biological: Microbiological sampling (swab collection)

Participants in the case group will undergo microbiological sampling consisting of four swabs: two rectal swabs, one oral swab, and one skin swab from the inguinal fold.

Participants in the control group will undergo a single rectal swab. The samples will be collected for microbiological analysis.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Qualitative and quantitative bacterial composition of the intestinal microbiota (molecular microbiology/PCR).
Time Frame: From enrollment to the collection of the four swabs: 24 to 48 hours.
From enrollment to the collection of the four swabs: 24 to 48 hours.

Secondary Outcome Measures

Outcome Measure
Time Frame
Mapping of E. faecalis colonization (urinary, digestive, and/or cutaneous) in patients diagnosed with E. faecalis bacteremia (EFIB);
Time Frame: From enrollment to the collection of the four swabs: 24 to 48 hours.
From enrollment to the collection of the four swabs: 24 to 48 hours.
Genomic characterization through core genome analysis of E. faecalis strains isolated from colonization sites and from blood cultures in the same patient diagnosed with EFIB;
Time Frame: From enrollment to the collection of the four swabs: 24 to 48 hours.
From enrollment to the collection of the four swabs: 24 to 48 hours.
Whole-genome characterization of E. faecalis strains isolated from colonization sites and those recovered from blood cultures in patients with EFIB;
Time Frame: From enrollment to the collection of the four swabs: 24 to 48 hours.
From enrollment to the collection of the four swabs: 24 to 48 hours.
Description of potential portals of entry for enterococci at the end of hospitalization for EFIB.
Time Frame: From enrollment to the collection of the four swabs: 24 to 48 hours.
From enrollment to the collection of the four swabs: 24 to 48 hours.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University Hospital, Clermont-Ferrand

Investigators

  • Principal Investigator: Magali VIDAL, University Hospital, Clermont-Ferrand

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

January 2, 2026

Primary Completion (Estimated)

December 31, 2028

Study Completion (Estimated)

December 31, 2028

Study Registration Dates

First Submitted

December 17, 2025

First Submitted That Met QC Criteria

December 17, 2025

First Posted (Estimated)

January 2, 2026

Study Record Updates

Last Update Posted (Actual)

January 9, 2026

Last Update Submitted That Met QC Criteria

January 7, 2026

Last Verified

December 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • RBHP 2025 VIDAL

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Infective Endocarditis (IE)

Clinical Trials on Microbiological sampling (swab collection)

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Mali

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe