Comparison of polymerase chain reaction and conventional methods in detecting methicillin-resistant Staphylococcus aureus

J Infect Dev Ctries. 2008 Feb 1;2(1):46-50. doi: 10.3855/jidc.321.

Abstract

Background: Accurate and rapid detection of methicillin-resistant Staphylococcus aureus is very important in a clinical laboratory setting to avoid treatment failure. Conventional methods were compared against the gold standard polymerase chain reaction (PCR) technique to determine the best combination of the routine procedures.

Methodology: Methicillin resistance was investigated in 416 clinical Staphylococcus aureus isolates by PCR, oxacillin agar screening (OAS), oxacillin disk diffusion (ODD) and cefoxitin disk diffusion (CDD) methods.

Results: Two hundred and ten (51%) out of 416 S. aureus strains were found to be mecA-positive by PCR. Sensitivity and specificity of the ODD, CDD and OAS methods were detected as follows: 100% and 89%, 99.50% and 100%, and 99.50% and 100%, respectively.

Conclusion: Combining the ODD and CDD methods could be a good choice for detecting methicillin resistance in S. aureus strains where mecA PCR cannot be performed.

Publication types

  • Comparative Study

MeSH terms

  • Cefoxitin
  • Disk Diffusion Antimicrobial Tests*
  • Humans
  • Methicillin-Resistant Staphylococcus aureus / classification
  • Methicillin-Resistant Staphylococcus aureus / genetics
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification*
  • Oxacillin
  • Polymerase Chain Reaction*
  • Sensitivity and Specificity
  • Staphylococcal Infections / drug therapy
  • Staphylococcal Infections / microbiology*

Substances

  • Cefoxitin
  • Oxacillin