Background: MRSA is responsible for the largest number of outbreaks in the hospital settings. MRSA causes wide spectrum of infection including sepsis/endocarditis, lower respiratory tract infections etc. Resistance to methicillin is due to the presence of an altered penicillin-binding protein called PBP2a resulting from acquisition of a chromosomal gene called mec A. Detection of MRSA is complicated due to its heterogeneous nature. Keeping in mind the increasing rate of infections caused by MRSA there is a need for rapid, accurate and reliable tests for the detection of MRSA so that antibiotic therapy and infection control measures can be initiated. The present study combined the use of cefoxitin disc diffusion as the standard method in supplementation with latex agglutination assay for MRSA detection.
Methods: cefoxitin disc diffusion method and latex agglutination test.
Results: By cefoxitin disc diffusion 90 strains were mecA positive and were labeled as MRSA and 110 were labeled as MSSA. By latex agglutination test all the 90 MRSA were identified as MRSA whereas of 110 MSSA S.aureus strains 109 were detected as MSSA.
Conclusion: cefoxitin disc diffusion is a good method but it should be supplemented with some other method so that no MRSA is missed. Latex agglutination test on the other hand gave results within 15 min and is able to detect even low levels of PBP2a.
