Molecular Analysis of Enterococcus Faecalis Isolates in a 4-year Period

Area of Science:

• Microbiology
• Infectious Diseases
• Genetics

Background:

• Enterococcus faecalis is a significant opportunistic pathogen, particularly in healthcare settings.
• Understanding the genetic diversity and virulence factors of E. faecalis is crucial for infection control.

Purpose of the Study:

• To characterize E. faecalis strains isolated from an Iranian Children's Hospital over a four-year period.
• To investigate the prevalence of virulence genes and genetic relatedness among these isolates.

Main Methods:

• Sixty-seven E. faecalis isolates were analyzed.
• Virulence genes were detected using molecular methods.
• Variable-number tandem repeat (VNTR) typing and multiple-locus variable-number tandem repeat analysis (MLVA) were employed for genetic characterization.

Main Results:

• High frequencies of virulence genes, including gelatinase (73%) and Enterococcus faecalis (62%), were observed.
• MLVA analysis of 67 isolates identified 52 VNTR patterns and 38 distinct MLVA types (MTs).
• Significant genetic diversity was found, with MLVA type 1 (MT1) identified as the predominant type across different hospital wards.

Conclusions:

• The study highlights the genetic diversity of E. faecalis strains circulating in a pediatric hospital setting.
• The prevalence of specific virulence genes and the dominance of MT1 suggest potential transmission patterns within the hospital.
• These findings provide valuable insights for targeted infection control strategies against E. faecalis in pediatric healthcare environments.