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

Adaleti R., Nakipoglu Y. , Karahan Z. C. , Tasdemir C., Kaya F.

JOURNAL OF INFECTION IN DEVELOPING COUNTRIES, cilt.2, ss.46-50, 2008 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Cilt numarası: 2 Konu: 1
  • Basım Tarihi: 2008
  • Sayfa Sayıları: ss.46-50


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.

Key Words

: Methicillin-resistant Staphylococcus aureus (MRSA), polymerase chain reaction (PCR), oxacillin disk diffusion,

cefoxitin disk diffusion, oxacillin agar screening.

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