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Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
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Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

Widespread emergence of methicillin resistance in community-acquired Staphylococcus aureus infections in Denver

Megan J Clancy1, Amy Graepler, Peter E Breese

  • 1Department of Internal Medicine, University of Colorado Health Sciences Center, Denver, CO. USA.

Southern Medical Journal
|December 15, 2005
PubMed
Abstract

Insights

Methicillin-resistant Staphylococcus aureus (MRSA) caused a sharp rise in outpatient skin infections. A single MRSA strain, USA 300, is responsible, necessitating alternative antibiotic treatments for skin infections.

Area of Science:

  • Infectious Diseases
  • Epidemiology
  • Microbiology

Background:

  • Outpatient Staphylococcus aureus infections show increasing methicillin resistance.
  • A local outbreak prompted an investigation into its epidemiology and outcomes.

Purpose of the Study:

  • To assess the epidemiology and outcomes of a local outbreak of methicillin-resistant Staphylococcus aureus (MRSA) infections.
  • To identify factors associated with MRSA in outpatient skin and soft tissue infections.

Main Methods:

  • Retrospective cohort study of outpatient skin and soft tissue infections.
  • Analysis of Staphylococcus aureus isolates from 2002 to mid-2004.
  • Pulsed field gel electrophoresis (PFGE) to characterize MRSA strains.

Main Results:

  • Methicillin resistance in outpatient S. aureus increased from 6% to 45% between 2002 and mid-2004.
  • Male sex and age over 18 were associated with methicillin resistance.
  • MRSA strains, related to USA 300, exhibited high quinolone resistance rates.

Conclusions:

  • A single MRSA strain (USA 300) is driving the increase in outpatient skin infections.
  • Patients infected often lack traditional risk factors for antibiotic-resistant strains.
  • Non-beta-lactam antibiotics are recommended for initial treatment of skin and soft tissue infections in high-MRSA prevalence areas.

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