Methicillin-resistant Staphylococcus aureus (MRSA) has become a ubiquitous bacterium in both the hospital and community setting. There are two major subclassifications of MRSA, community-acquired and healthcare-acquired, each with differing pathogenicity and management. MRSA is increasingly responsible for infections in otherwise healthy, active adults. Local outbreaks affect both professional and amateur athletes and there is increasing public awareness of the issue. Health-acquired MRSA has major cost and outcome implications for patients and hospitals. The increasing prevalence and severity of MRSA means that the orthopaedic community should have a basic knowledge of the bacterium, its presentation and options for treatment. This paper examines the evolution of MRSA, analyses the spectrum of diseases produced by this bacterium and presents current prevention and treatment strategies for orthopaedic infections from MRSA.

To improve the clinical outcome of Staphylococcus aureus septicemia, the early selection of appropriate antibiotic treatment is crucial. Molecular diagnostics represents an attractive approach for the rapid identification of S. aureus and the determination of its methicillin (meticillin) resistance. In direct comparison to other molecular assays (sa442 and mecA real-time PCRs) and standard laboratory procedures, we evaluated the BD GeneOhm StaphSR assay for its use in the detection of S. aureus and methicillin-resistant S. aureus (MRSA) from spiked blood culture bottles (n ‫؍‬ 134). In the case of detecting S. aureus (n ‫؍‬ 90; for methicillin-susceptible S. aureus, n ‫؍‬ 45; for MRSA, n ‫؍‬ 45), the BD GeneOhm StaphSR assay had a sensitivity and a specificity of 100% each (95% confidence intervals [CIs], 96.0 to 100% and 82.4 to 100%, respectively). For MRSA (n ‫؍‬ 45), the test was 95.6% (95% CI, 84.9 to 99.5%) sensitive and 95.3% (95% CI, 86.9 to 99.0%) specific. Overall, five discrepant results arose with this assay due to the presence of methicillin-susceptible, revertant MRSA strains (3/45) and MRSA strains that were not detected by the BD GeneOhm StaphSR assay (2/45). Compared to other real-time PCR-based molecular approaches and to conventional standard laboratory methods, the BD GeneOhm StaphSR turned out to be an appropriate diagnostic tool for a rapid (ϳ1.5 h), preliminary identification of S. aureus and MRSA from blood cultures.