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Updated: Apr 14, 2026
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Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
Published on: May 8, 2013
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[Phenotypic methods for detection of methicillin-resistant Staphylococcus aureus].
G Horna1, L Astocondor, J Jacobs
1Gertrudis Horna, Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano He-redia, Lima Perú. Av.Honorio Delgado # 430 - Urb Ingenieria - SMP - Lima- Perú. sara.horna@upch.pe.
Summary
The cefoxitin disc diffusion test accurately identifies methicillin-resistant Staphylococcus aureus (MRSA) by detecting the mecA gene. This method is a viable alternative to PCR for MRSA screening, especially in resource-limited settings.
Area of Science:
- Clinical microbiology
- Molecular diagnostics
- Antimicrobial resistance
Context:
- Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant healthcare challenge.
- The mecA gene is a key marker for MRSA identification.
- Current screening methods include oxacillin agar and cefoxitin disc diffusion.
Purpose:
- To compare the sensitivity and specificity of cefoxitin disc diffusion (30 μg) against oxacillin agar screening for detecting the mecA gene in S. aureus isolates.
- To evaluate cefoxitin disc diffusion as a potential alternative for MRSA detection.
Summary:
- A study involving 331 S. aureus blood culture isolates from Lima hospitals compared cefoxitin disc diffusion, oxacillin agar screening, and PCR for mecA gene detection.
- The mecA gene was found in 50% of isolates.
- Cefoxitin disc diffusion demonstrated 96.3% sensitivity and 90.9% specificity.
Impact:
- Cefoxitin disc diffusion test shows strong correlation with PCR-based mecA gene detection.
- This test is a reliable alternative for MRSA detection, particularly beneficial in settings with limited resources.
- Improved diagnostic capabilities for MRSA can lead to better patient management and infection control.
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