Phenotypic and Genotypic Variations of Enterococcus Spp

April 16, 2023 updated by: Mai Gamal Abdel Naser Abbas Khalifa, Sohag University

Phenotypic and Genotypic Variations of Enterococcus Spp. Isolated From Patients With Hospital Acquired Infections in Sohag University Hospitals, Egypt

Enterococci are Gram-positive facultative anaerobic cocci arranged in short and medium chains. Enterococci reside in the gastrointestinal tract and usually function commensally with humans. They can, however, cause several infections, such as urinary tract infections (UTIs), intra-abdominal infection, bacteremia, or endocarditis.

Among many species identified, E. faecalis and E. faecium are the most common species capable of causing infection and posing a threat of antimicrobial resistance, with E. faecalis accounting for the majority of infections.

Study Overview

Detailed Description

Enterococci are Gram-positive facultative anaerobic cocci arranged in short and medium chains.

Enterococci reside in the gastrointestinal tract and usually function commensally with humans. They can, however, cause several infections, such as urinary tract infections (UTIs), intra-abdominal infection, bacteremia, or endocarditis.

Among many species identified, E. faecalis and E. faecium are the most common species capable of causing infection and posing a threat of antimicrobial resistance, with E. faecalis accounting for the majority of infections.

Pathogenic species of enterococci express many virulence factors such as adhesins, gelatinase, Enterococcus surface protein, aggregation substances and cytolysins along with biofilm formation. These factors enhance the ability of the pathogen to invade, attach and survive through the acquisition of nutrients in the host tissue. Their presence in drug resistant strains increases the severity of the infection

Enterococci are intrinsically resistant to antibiotics such as aminoglycosides and β-lactam-based antibiotics. Moderate resistance to aminoglycosides is due to the intrinsic low permeability of the enterococcal cell wall to the large aminoglycoside molecules and is more prevalent in E. faecium than E. faecalis. Intrinsic β-lactam resistance is due to the overexpression of penicillin-binding proteins with low affinity for β-lactams, which makes E. faecalis more resistant to penicillin than E. faecium

Moreover, enterococci can readily acquire resistance to antimicrobials, and vancomycin-resistant enterococci (VRE) are among the priority pathogens for which new antibiotics are needed.

In addition, biofilm formation is one of the strategies for the enterococci to evade the host's immune response and the inhibitory or killing effects of antibiotics.

This self-produced extracellular matrix also provides a suitable microenvironment for enterococci to grow and facilitates the transmission of mobile genetic elements (MGEs) between bacteria. Enterococcal biofilms have been implicated in indwelling device-related infections such as prosthetic valve endocarditis, prosthetic joint infections and catheter-related infections.

Biofilm forming bacteria show resistance to many antibiotics and immune response which results in treatment failure. Given the difficulty of treating and eradicating biofilm associated infections, there is an unmet need for therapeutic options other than antibiotics to prevent biofilm formation.

Nanoparticles are attracting attention given their very small size and various antibacterial properties. Nanoparticles can interact with bacteria per unit area, which can make the antibacterial activity of nanoparticles more powerful. Nanoparticles can also initiate several bactericidal pathways, such as disrupting the bacterial membrane and release of intracellular components, making it difficult for bacteria to become resistant.

Study Type

Observational

Enrollment (Anticipated)

100

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 Contact Backup

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

1 month to 90 years (Child, Adult, Older Adult)

Accepts Healthy Volunteers

N/A

Sampling Method

Non-Probability Sample

Study Population

All the selected patients will be subjected to complete history taking (personal, clinical, associated comorbidities, history of drug intake, and length of hospital stay before sampling).

* Collected samples will be transported to the Medical Microbiology and Immunology research laboratory as soon as possible.

Description

Inclusion Criteria:

  • All patients suffering from infections that can be caused by Enterococci.

Exclusion Criteria:

  • All patients suffering from infections that aren't caused by Enterococci

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

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
samples containing Enterococci

Isolates of Enterococci will be identified by Gram staining, colony morphology, catalase test, and growth on Bile Esculin agar. All isolates will be identified to species level using Vitek2 automated system Strains confirmed as Enterococci will be examined for their antibiotic susceptibility by modified Kirby Bauer's disc diffusion method on MuellerHinton Agar.

The biofilm formation activity of Enterococci isolates will be tested using the microtiter plate technique Detection of the effect of nanoparticles on the antibiotic susceptibility profile of Enterococci. Detection of the effect of nanoparticles on the biofilm producing Enterococci. Molecular identification of some virulence factors genes and antibiotic resistance genes of Enterococci using PCR

  • Samples will be transported to Medical Microbiology and Immunology Laboratory and will be inoculated on MacConkey medium.
  • Pink colonies will be inoculated on bile esculin agar medium.
  • Enterococci produce blackening of the agar
The growing colonies on bile esculin agar medium will be examined microscopically after staining by Gram stain.
  • Catalase test.
  • Salt tolerance test
Automated identification of Enterococci will be done with VITEK2 system.
Strains confirmed as Enterococci will be examined for their antibiotic susceptibility by modified Kirby Bauer's disc diffusion method on Mueller-Hinton Agar.
The effect of nanoparticles on Enterococci antimicrobial resistance pattern
The biofilm formation activity of Enterococci isolates will be tested using the microtiter plate technique
Molecular identification of some virulence factors genes and antibiotic resistance genes of Enterococci using PCR
samples with bacteria other than enterococci
  • Samples will be transported to Medical Microbiology and Immunology Laboratory and will be inoculated on MacConkey medium.
  • Pink colonies will be inoculated on bile esculin agar medium.
  • Enterococci produce blackening of the agar
The growing colonies on bile esculin agar medium will be examined microscopically after staining by Gram stain.
  • Catalase test.
  • Salt tolerance test
Automated identification of Enterococci will be done with VITEK2 system.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Isolation and identification of Enterococci from different clinical samples
Time Frame: from April 2023 to December 2023
Isolation and identification of Enterococci from different clinical samples (pus, urine, urinary catheter samples, stool, wound swabs, sputum, central venous catheter samples) will be collected under aseptic precautions from patients admitted at different departments at Sohag university hospitals.
from April 2023 to December 2023
Demonstration of Enterococci antibiotic susceptibility profile
Time Frame: from April 2023 to December 2023
Strains confirmed as Enterococci will be examined for their antibiotic susceptibility by modified Kirby Bauer's disc diffusion method on Mueller-Hinton Agar.
from April 2023 to December 2023
Detection of strains of Enterococci which produce biofilm
Time Frame: from April 2023 to December 2023
The biofilm formation activity of Enterococci isolates will be tested using the microtiter plate technique
from April 2023 to December 2023
Studying the effect of nanoparticles on Enterococci antimicrobial resistance pattern
Time Frame: from April 2023 to December 2023
Inhibition zones of all groups will be compared to detect the effect of nanoparticles on Enterococci antimicrobial resistance pattern.
from April 2023 to December 2023
Studying the effect of nanoparticles on Enterococci biofilm producing ability
Time Frame: from December 2023 to March 2024
The effect of nanoparticles on Enterococci biofilm producing ability
from December 2023 to March 2024
Genotypic characterization of Enterococci.
Time Frame: rom December 2023 to March 2024
Molecular identification of some virulence factors genes and antibiotic resistance genes of Enterococci using polymerase chain reaction.
rom December 2023 to March 2024

Collaborators and Investigators

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

Investigators

  • Study Chair: Mona F Mohamed, professor, Sohag University
  • Study Chair: Wesam A Abu El wafa, Sohag University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

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 (Actual)

April 1, 2023

Primary Completion (Anticipated)

December 31, 2023

Study Completion (Anticipated)

March 30, 2024

Study Registration Dates

First Submitted

February 20, 2023

First Submitted That Met QC Criteria

February 20, 2023

First Posted (Actual)

March 2, 2023

Study Record Updates

Last Update Posted (Actual)

April 19, 2023

Last Update Submitted That Met QC Criteria

April 16, 2023

Last Verified

April 1, 2023

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

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.

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