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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

Staphylococcus aureus ocular isolates from symptomatic adverse events: antibiotic resistance and similarity of

Tracey L Schubert1, Emma B H Hume, Mark D P Willcox

  • 1The School of Optometry and Vision Science, University of New South Wales, NSW, Australia. t.schubert@ier.org.au

Clinical & Experimental Optometry
|February 15, 2008
PubMed
Abstract

Insights

Staphylococcus aureus causing eye infections shows increasing antibiotic resistance, particularly in the USA. Isolates from corneal issues are more resistant than those from conjunctivitis, suggesting virulence may correlate with resistance.

Area of Science:

  • Ophthalmology
  • Microbiology
  • Infectious Diseases

Background:

  • Staphylococcus aureus is a primary cause of microbial keratitis.
  • Increasing antibiotic resistance in ocular S. aureus strains, including fluoroquinolones, is a growing concern.
  • Understanding S. aureus isolate characteristics is crucial for effective treatment.

Purpose of the Study:

  • To assess current antibiotic susceptibilities of ocular S. aureus isolates.
  • To investigate relationships between isolates from different ocular adverse events.
  • To determine if isolates with similar antimicrobial susceptibilities are related.

Main Methods:

  • Analyzed 55 S. aureus strains from ocular adverse events.
  • Assessed antibiotic susceptibility using the disc diffusion (CDS) method.
  • Typed isolates using PCR-ribotyping and pulsed-field gel electrophoresis (PFGE).

Main Results:

  • Ocular S. aureus from the USA showed higher antibiotic resistance than those from Australia or India (p<0.05).
  • Isolates from ulcerative keratitis were more resistant than those from conjunctivitis.
  • PFGE and ribotyping revealed geographical and adverse event-specific clustering of related isolates.

Conclusions:

  • Related S. aureus isolates within geographical regions cause similar adverse events.
  • Genetic differences exist between isolates causing corneal versus conjunctivitis.
  • Increased antibiotic resistance in corneal isolates, especially from the USA, may correlate with higher virulence.

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