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Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
14:04

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

Glycopeptide and oxacillin activity against Staphylococcus aureus isolates at a tertiary care center in Lebanon

Souha S Kanj1, Patricia A Ghaleb, George F Araj

  • 1Department of Internal Medicine, American University of Beirut Medical Center, Beirut.

Le Journal Medical Libanais. the Lebanese Medical Journal
|May 11, 2005
PubMed
Abstract

Insights

This study found no glycopeptide-intermediate Staphylococcus aureus (GISA) in Lebanon, despite high rates of methicillin-resistant S. aureus (MRSA). All MRSA strains remained susceptible to vancomycin and teicoplanin.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Clinical Medicine

Background:

  • Emergence of glycopeptide-intermediate Staphylococcus aureus (GISA) is a global concern.
  • Limited data exists on GISA prevalence in Lebanon.
  • This study addresses the lack of local data on antimicrobial resistance in Staphylococcus aureus.

Purpose of the Study:

  • To determine antimicrobial susceptibility patterns of Staphylococcus aureus isolates in Lebanon.
  • To investigate the prevalence of methicillin-resistant S. aureus (MRSA) and glycopeptide-intermediate S. aureus (GISA).
  • To assess the minimum inhibitory concentrations (MICs) for oxacillin, vancomycin, and teicoplanin.

Main Methods:

  • Analysis of 147 consecutive clinical isolates of S. aureus from a tertiary care center in Lebanon.
  • Categorization of isolates based on oxacillin agar screen and disk diffusion tests.
  • Determination of MICs for oxacillin, vancomycin, and teicoplanin using E-test.

Main Results:

  • 108 isolates were MRSA (73.5%) and 39 were methicillin-susceptible S. aureus (MSSA).
  • MRSA strains showed high MICs for oxacillin but remained susceptible to vancomycin (MIC50/90: 2/3 μg/mL) and teicoplanin (MIC50/90: 1/1.5 μg/mL).
  • No GISA isolates were detected.

Conclusions:

  • Lebanese MRSA strains exhibit high oxacillin resistance but remain susceptible to vancomycin and teicoplanin.
  • The absence of GISA suggests current treatment strategies remain effective in this region.
  • Continued surveillance for antimicrobial resistance in S. aureus is crucial.

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