Comparison of different laboratory methods for detection of methicillin resistant Staphylococcus aureus

Abstract

OBJECTIVE: The aim of this study was to compare four different methods for detection of methicillin resistant Staphylococcus aureus (MRSA).

DESIGN: The clinical specimens including urine, blood, wound, high vaginal swabs, sputum, semen, ear swabs and tracheal tube aspirates ware processed for isolation of S. aureus.

SETTINGS: The samples were obtained from patient attending Murtala Muhammad Specialist hospitalKano,Nigeria.

SUBJECTS: 495 Strains of S. aureus were testes with four different methods i. e disk diffusion, oxacillin screen agar, E – test and latex agglutination for methicillin resistance.

RESULTS: Of 495tested S. aureus: E – test revealed that 128 isolates were MRSA. Oxacillin screen agar showed two fail positive MRSA. The sensitivity and Specificity of oxacillin screen agar methods was 99% and 98% r

Respectively. The sensitivity and specificity for screen latex agglutination method was 100% and 100% respectively. Results of susceptibility testing by disk diffusion methods in comparison with other methods were conflicting.

CONCLUSION: MRSA Latex agglutination Kit is a reliable alternative for detection of MRSA in clinical laboratory ware MIC detection of MRSA or molecular methods are not available. Also Oxacillin screen agar offers an interesting new approach to early detection of MRSA.