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Comparison of ampicillin/sulbactam and amoxicillin/clavulanic acid for detection of borderline oxacillin-resistantStaphylococcus aureus

  • H. Liu
  • N. Lewis
Notes

Abstract

Borderline oxacillin-resistantStaphylococcus aureus (BORSA) may be misidentified as intrinsically methicillin-resistantStaphylococcus aureus (MRSA) in the clinical laboratory. Under disk diffusion testing conditions designed to maximize detection of MRSA (incubation at 32 °C, pre-induction with methicillin, or plating on 4 % NaCl-supplemented agar), BORSA strains also tend to appear resistant to semisynthetic penicillins. Under these conditions, ampicillin/sulbactam appears to be more accurate than amoxicillin/clavulanic acid for differentiating BORSA from MRSA.

Keywords

Internal Medicine Agar Penicillin Clinical Laboratory Disk Diffusion 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Friedr. Vieweg & Sohn Verlagsgesellschaft mbH 1992

Authors and Affiliations

  • H. Liu
    • 1
  • N. Lewis
    • 1
  1. 1.Department of Medicine, Presbyterian Medical CenterUniversity of PennsylvaniaPhiladelphiaUSA

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