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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
12:18

Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)

Published on: February 9, 2011

Methicillin-resistant staphylococci

H F Chambers1

  • 1Medical Service, San Francisco General Hospital, California.

Clinical Microbiology Reviews
|April 1, 1988
PubMed

Insights

Methicillin-resistant staphylococci (MRS) exhibit variable resistance due to unique penicillin-binding protein 2a (PBP2a). Detection and treatment challenges are discussed, with vancomycin as the preferred therapy.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Methicillin-resistant staphylococci (MRS) emerged shortly after methicillin's introduction.
  • These strains display significant heterogeneity in expressing resistance traits.
  • This variability complicates accurate detection and treatment strategies.

Purpose of the Study:

  • To describe conditions influencing heterogeneous methicillin resistance expression in staphylococci.
  • To review susceptibility testing methods for MRS detection.
  • To discuss current and emerging treatment options for MRS infections.

Main Methods:

  • Characterization of penicillin-binding protein 2a (PBP2a) and its encoding mec determinant.
  • Evaluation of various antimicrobial susceptibility testing methodologies.
  • Review of clinical data on treatment outcomes for MRS infections.

Main Results:

  • Methicillin resistance is linked to PBP2a production, encoded by the mec determinant.
  • PBP2a is inactivated only at high beta-lactam antibiotic concentrations.
  • Heterogeneous resistance expression poses significant challenges for reliable laboratory detection.

Conclusions:

  • Understanding PBP2a and mec determinant is crucial for elucidating resistance mechanisms.
  • Standardized susceptibility testing guidelines are essential for accurate MRS identification.
  • Vancomycin remains the primary treatment, with new agents showing promise for resistant strains.

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