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Published on: February 9, 2011

Staphylococcus aureus causing tropical pyomyositis, Amazon Basin, Peru

Coralith García1, Marie Hallin, Ariane Deplano

  • 1Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru. coralith.garcia@upch.pe

Emerging Infectious Diseases
|December 25, 2012
PubMed

Insights

This study identified Staphylococcus aureus strains causing tropical pyomyositis in Peru. Sequence type 25 strains carrying Panton-Valentine leukocidin genes are circulating in South America.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Tropical Medicine

Background:

  • Tropical pyomyositis is a bacterial infection primarily affecting skeletal muscles.
  • Staphylococcus aureus is a common pathogen, but its prevalence in tropical pyomyositis in the Amazon Basin is less understood.
  • Understanding the genetic characteristics of S. aureus strains is crucial for effective treatment and public health strategies.

Purpose of the Study:

  • To characterize Staphylococcus aureus isolates from patients with tropical pyomyositis in the Peruvian Amazon.
  • To identify specific genetic markers, such as Panton-Valentine leukocidin genes and multilocus sequence types, within these isolates.
  • To determine the potential circulation of specific S. aureus sequence types in this tropical region.

Main Methods:

  • Collection and microbiological analysis of 12 Staphylococcus aureus isolates from patients with tropical pyomyositis.
  • Methicillin susceptibility testing.
  • Detection of Panton-Valentine leukocidin-encoding genes using molecular methods.
  • Multilocus sequence typing (MLST) to determine the genetic lineage of the isolates.
  • Analysis for the presence of enterotoxin genes.

Main Results:

  • All 12 Staphylococcus aureus isolates were susceptible to methicillin.
  • Eleven out of 12 isolates (91.7%) harbored Panton-Valentine leukocidin-encoding genes.
  • Five isolates (41.7%) belonged to multilocus sequence type 25 (ST25).
  • These ST25 isolates also possessed a wide array of enterotoxin genes.
  • No methicillin-resistant Staphylococcus aureus (MRSA) was detected.

Conclusions:

  • Methicillin-susceptible Staphylococcus aureus (MSSA) strains are implicated in tropical pyomyositis in the Peruvian Amazon.
  • The high prevalence of Panton-Valentine leukocidin genes in these MSSA isolates is noteworthy.
  • The findings strongly suggest that multilocus sequence type 25 is a significant and circulating lineage in tropical South America, associated with pyomyositis and carrying virulence factors.

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