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Toxigenic profile of methicillin-sensitive and resistant Staphylococcus aureus isolated from special groups

Camila Sena Martins de Souza1,2, Carlos Magno Castelo Branco Fortaleza3, Claudia Lima Witzel4,5

  • 1Department of Microbiology and Immunology, Botucatu Biosciences Institute, UNESP-Univ Estadual Paulista, Botucatu, SP, Brazil. camilasena07@hotmail.com.

Annals of Clinical Microbiology and Antimicrobials
|February 17, 2016
PubMed
Abstract

Insights

Toxigenic Staphylococcus aureus strains, including methicillin-sensitive (MSSA) and methicillin-resistant (MRSA) types, are prevalent in asymptomatic carriers. Cytotoxin genes were most common among these S. aureus isolates.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Genetics

Background:

  • Staphylococcus aureus is a prevalent pathogen causing infections in diverse populations.
  • The dissemination of toxigenic S. aureus strains poses a significant public health concern.
  • Understanding the toxigenic potential of S. aureus is crucial for infection control.

Purpose of the Study:

  • To determine the toxigenic gene profiles of methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA).
  • To investigate these profiles in patients with skin infections, asymptomatic carriers (elderly in nursing homes), and prison inmates.

Main Methods:

  • Polymerase chain reaction (PCR) was employed for gene detection.
  • Specific genes targeted included mecA, enterotoxin genes (sea, seb, sec), exfoliative toxins (eta, etb), toxic shock syndrome toxin 1 (tst), Panton-Valentine leukocidin (lukS-PV, lukF-PV), and alpha- and delta-hemolysins (hla, hld).

Main Results:

  • A significant prevalence of toxigenic genes was observed in S. aureus isolates from asymptomatic individuals.
  • Cytotoxin genes (hla, hld) showed a higher prevalence among S. aureus isolates.
  • Panton-Valentine leukocidin was detected only in MSSA from skin infection patients, and tst was found exclusively in MSSA from prison inmates.

Conclusions:

  • Asymptomatic carriers harbor a significant proportion of toxigenic MSSA and MRSA strains.
  • Cytotoxin genes are frequently present in S. aureus isolates from various populations, including asymptomatic carriers.

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