Assessment of methicillin resistant Staphylococcus Aureus detection methods: analytical comparative study

Area of Science:

• Clinical microbiology
• Infectious diseases
• Antimicrobial resistance

Background:

• Methicillin resistance in Staphylococcus aureus (MRSA) is heterogeneous, impacting detection test efficiency.
• Accurate MRSA detection is crucial for effective treatment and infection control.

Purpose of the Study:

• To evaluate and compare the performance of four phenotypic tests for detecting MRSA.
• To determine the most reliable methods for routine MRSA screening.

Main Methods:

• Comparative analytical study involving Staphylococcus aureus strains from Sudanese patients.
• Conventional identification and PCR confirmation of S. aureus and the mecA gene.
• Assessment of oxacillin resistance screen agar base (ORSAB), oxacillin disc, cefoxitin disc, and MRSA-latex agglutination test against PCR as the gold standard.

Main Results:

• MRSA-latex agglutination demonstrated 100% sensitivity and specificity.
• Cefoxitin disc showed 98.48% sensitivity and 100% specificity.
• Oxacillin disc and ORSAB exhibited lower accuracy, with results influenced by incubation time and temperature.

Conclusions:

• MRSA-latex agglutination and cefoxitin disc diffusion tests are recommended for routine MRSA detection.
• These methods provide reliable and accurate results for clinical laboratories.