Abstract

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) has currently become an important healthcare concern as its resistant to multiple antibiotics. Currently, it’s one of the major hospitals acquired and community acquired pathogen causing blood stream infections(BSI). Therefore, rapid identification of MRSA in clinical specimens is essential for timely decision on effective antimicrobial drug therapy. Aim: To detect the prevalence of MRSA isolates isolated from blood culture samples. To compare phenotypic methods; Mannitol salt agar (MSA), Cefoxitin disk diffusion (CDD) & Oxacillin resistant screening agar base (ORSAB) with CHROMagar MRSA. Materials and Methods: An Laboratory based cross-sectional study was carried out in the Microbiology department, UCMS and GTBH from January 2024 to April 2024 were included and further characterized. All the isolates were cultured in MSA, blood agar and MacConkey agar. The phenotypic methods used for confirming MRSA was Cefoxitin disc (30µg) diffusion, CHROMagarTMMRSA andORSAB for phenotypic identification. Results: Out of 328 isolates of S. aureus, 151(73. 3%) isolates were MRSA detected by CDD method, CHROMagarTM MRSA and ORSAB. The sensitivity of chromogenic media i. eCHROMagarTM MRSA and ORSAB is 94. 2% and 97. 2% respectively. All MRSA isolated were susceptible to Vancomycin, Linezolid and resistant to commonly used antibiotics. Conclusion: CHROMagarTM MRSA and ORSAB is found to be accurate for the detection of MRSA. It is reliable, easy to perform, less time-consuming, and cost-effective. It is an affordable alternative to the conventional method of detection of MRSA in resource-poor settings.

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