Aim: Worldwide, an estimated 2 billion healthy people carry Staphylococcus aureus (SA) and of these, up to 53 million are thought to carry methicillin-resistant SA (MRSA). MRSA bacteremia patients are more critical to manage and timely introduction of antibiotics is life-saving. The aim of the study was to elucidate the prevalence of MRSA bacteremia in different units of Teaching Hospital, Anuradhapura (THA), Sri Lanka and assess the clinical characteristics and associated mortality related to timely introduction of vancomycin therapy.

Materials and Methods: The data on MRSA bacteremia which were obtained from THA, for the period of March 2012 to December 2013 were statically analyzed emphasizing the unit-wise prevalence, severity, and comorbidity and timely introduction of vancomycin therapy.

Results: The laboratory records of total 13,260 blood cultures were analyzed. Of those, MRSA bacteremia was detected in 61 cultures (9.3%). The highest prevalence of MRSA bacteremia was observed in the nephrology unit. The survival rate of the patients when the vancomycin therapy started before 24 h of receiving the blood culture report was 94.9% and in the instances of the treatment started after 24 h of blood culture report, the survival rate decreased down to 50%. High Pitt Bacteraemia score (PBS) (p<0.05) and initiation of vancomycin therapy after 24 h following the receipt of blood culture report (p<0.05) independently affected the MRSA bacteremic patient's 7th day mortality. Having comorbidities have not shown significant impact on 7th day mortality.

Conclusion: The start of vancomycin therapy as earlier as possible following arrival of antibacterial susceptibility test reduces the likelihood of mortality.

Keywords: MRSA bacteremia, timing of vancomycin, severity.

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