JOURNAL OF INFECTION IN DEVELOPING COUNTRIES, cilt.2, sa.1, ss.46-50, 2008 (SCI-Expanded)
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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