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Prevalence of Genes Encoding Bi-Component Leukocidins among Clinical Isolates of Methicillin Resistant Staphylococcus

Sa Havaei1, S Ohadian Moghadam, Mr Pourmand

  • 1Dept. of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Iran.

Iranian Journal of Public Health
|November 1, 2012
PubMed
Abstract

Insights

Panton-Valentine leukocidin (PVL) and other bi-component leukocidins are prevalent in Methicillin-Resistant Staphylococcus aureus (MRSA) infections. This study found high rates of luk-PV and luk-E/D in MRSA isolates, highlighting the need for timely diagnosis and treatment.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Molecular Biology

Background:

  • Staphylococcus aureus is a significant human pathogen, frequently causing hospital-acquired infections.
  • Bi-component toxins, including Panton-Valentine leukocidin (PVL), are virulence factors produced by S. aureus.
  • PVL is associated with severe tissue damage, such as necrosis and leukocyte destruction.

Purpose of the Study:

  • To investigate the prevalence of bi-component leukocidin genes (luk-PV and luk-E/D) in Methicillin-Resistant Staphylococcus aureus (MRSA) isolates.
  • To understand the distribution of these toxin genes in clinical staphylococcal infections.

Main Methods:

  • 143 S. aureus isolates were collected from hospitals affiliated with Tehran University of Medical Sciences.
  • Polymerase chain reaction (PCR) was employed to detect the presence of luk-PV and luk-E/D genes.
  • Antibiotic susceptibility testing was performed using the disk diffusion method.

Main Results:

  • Out of 149 S. aureus isolates analyzed, 24.2% tested positive for the luk-PV gene.
  • A higher prevalence was observed for the luk-E/D genes, with 73.8% of isolates testing positive.
  • The study identified PVL-positive MRSA isolates, indicating their circulation in the studied healthcare settings.

Conclusions:

  • PVL-positive MRSA isolates are highly prevalent in the evaluated hospitals.
  • Infections caused by these bacteria can lead to severe outcomes, including extensive necrosis, leukopenia, and mortality.
  • Early diagnosis and appropriate treatment are crucial to prevent disease progression and reduce fatalities.
Keywords:
Bi-component leukocidinIranMethicillin-resistant Staphylococcus aureusStaphylococcal infections

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