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A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
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A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues

Published on: February 19, 2019

Prevalence of genes encoding extracellular virulence factors among meticillin-resistant Staphylococcus aureus

P Sauer1,2, J Síla2, T Štosová2

  • 1University Hospital, Olomouc, Czech Republic.

Journal of Medical Microbiology
|March 20, 2008
PubMed

Insights

This study investigated virulence factors in methicillin-resistant Staphylococcus aureus (MRSA) infections. Most MRSA isolates carried virulence genes, but specific toxin genes were absent, suggesting complex infection dynamics.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Genetics

Background:

  • Staphylococcus aureus strains, particularly methicillin-resistant Staphylococcus aureus (MRSA), can cause severe infections.
  • Virulence factors play a crucial role in the pathogenesis and progression of S. aureus infections.
  • Understanding the prevalence of specific virulence markers is essential for managing MRSA infections.

Purpose of the Study:

  • To determine the antibiotic susceptibility of MRSA isolates.
  • To screen for the presence and distribution of 13 extracellular virulence factor genes in MRSA isolates from hospitalized patients.
  • To analyze the association between virulence markers and sample types.

Main Methods:

  • Antibiotic susceptibility testing was performed on 100 MRSA isolates.
  • Polymerase chain reaction (PCR) was used to screen for 13 specific virulence genes (tst, pvl, eta, etb, sea, seb, sec, sed, see, seg, seh, sei, sej).
  • Isolates were obtained from various sample types from patients at the University Hospital in Olomouc, Czech Republic.

Main Results:

  • Eighty-nine percent of the 100 screened MRSA isolates were positive for at least one virulence gene.
  • Genes encoding for exfoliative toxin B (etb), Panton-Valentine leukocidin (pvl), staphylococcal enterotoxin O (see), and staphylococcal enterotoxin H (seh) were not detected in any of the isolates.
  • No significant differences were observed in the distribution of detected virulence determinants across different sample types.

Conclusions:

  • The majority of hospital-acquired MRSA isolates harbor virulence genes, contributing to infection severity.
  • The absence of specific virulence genes like pvl and etb in this MRSA cohort warrants further investigation into their epidemiological significance.
  • Virulence factor profiles appear consistent across various sample types in this patient population.

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