This article reviews recent clinical evidence for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. Vancomycin remains the initial antibiotic of choice for the treatment of patients with MRSA bacteremia and endocarditis due to isolates with vancomycin minimum inhibitory concentration ≤2 μg/mL, whereas daptomycin is an effective alternative, and ceftaroline seems promising. Treatment options for persistent MRSA bacteremia or bacteremia due to vancomycin-intermediate or vancomycin-resistant strains include daptomycin, ceftaroline, and combination therapies. There is a critical need for high-level evidence from clinical trials to allow optimally informed decisions in the treatment of MRSA bacteremia and endocarditis.

Glycopeptides are widely regarded, except in bacteraemic pneumonia, as the drugs of choice for MRSA bacteraemia111,156 although it is not always clear that comparator drugs were active against MRSA.193,194 There is some evidence that vancomycin is less satisfactory for MSSA than β-lactams and if vancomycin has been used empirically because of a need to provide effective antibacterials for MRSA, treatment may be changed to an active β-lactam. Data suggesting the superiority of β-lactam antibiotics comes from studies in right-sided endocarditis195 and also bacteraemia.73 In the latter study, in MSSA bacteraemia, both presence of endocarditis and therapy with vancomycin independently predict relapse or persistence of bacteraemia, even when iv catheters have been removed. Treatment with nafcillin was not associated with persistent bacteraemia or relapse. High relapse rates with vancomycin treatment and the failure to remove catheters have also been reported by others in patients with S. aureus bacteraemia, including both MRSA and MSSA, in the absence of endocarditis.73,75 MRSA infection in the presence of haemodialysis is also associated with a high incidence of endocarditis and septic arthritis with similar associations with leaving an intravascular catheter in situ and either with MRSA specifically or possibly with vancomycin therapy,74 and with a higher all-cause mortality at 3 months and much higher costs than MSSA bacteraemias.61 Improved antibiotic and infection control management in dialysis centres may therefore be of particular importance. Vancomycin is preferred to teicoplanin for treatment of S. aureus, including MRSA, bacteraemia unless teicoplanin levels are measured or high dosages (>6 mg/kg and probably 800 mg/day) are used empirically. Early studies with low dosages (200 mg/day) of teicoplanin without the use of loading doses were complicated by failure196 and doses up to 1200 mg/day may be needed87 but are expensive.
It has been suggested that using rifampicin with vancomycin improves outcome in uncomplicated bacteraemia but this comes from one uncorroborated study.149 Fusidic acid in combination with vancomycin may be relevant as an alternative to rifampicin. There is no evidence that the use of aminoglycosides with glycopeptides improves outcome in MRSA bacteraemia or endocarditis, and using aminoglycosides with vancomycin should be avoided, where possible, because of the risk of increased toxicity.197–199

Vancomycin and daptomycin are options for the initial treatment of patients with methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. Treatment options for persistent MRSA bacteremia or bacteremia due to vancomycin-intermediate or vancomycin-resistant strains include daptomycin, ceftaroline, and combination therapies. There is a critical need for high-level evidence from clinical trials to allow optimally informed decisions in the treatment of MRSA bacteremia.

Methicillin-resistant Staphylococcus aureus (MRSA) continues to be associated with significant morbidity and mortality. Vancomycin was the "gold standard" of treatment for serious MRSA infections; however, the emergence of less-susceptible strains, poor clinical outcomes, and increased nephrotoxicity with high-dose therapy are challenging its current role as first-line therapy. Linezolid is recommended for PO or IV treatment of skin and skin structure infections (SSSIs) and pneumonia caused by MRSA. Daptomycin (IV) should be considered in patients with MRSA bacteremia and right-sided endocarditis as well as in complicated SSSIs, but should not be used to treat MRSA pneumonia. Tigecycline and telavancin are alternative (IV) treatments for SSSIs caused by MRSA; however, safety concerns have limited use of these agents. Ceftaroline is the newest of the approved parenteral agents for SSSIs caused by MRSA. Several investigational agents with activity against drug-resistant gram-positive pathogens are being developed primarily for treatment of MRSA infections, including tedizolid, dalbavancin, and oritavancin.

Community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infection has become epidemic. Skin and soft-tissue infections (SSTIs) are the most frequent forms of the disease. Obtainment of culture specimens is important for documentation of the presence of MRSA and for susceptibility testing to guide therapy. Purulent lesions should be drained whenever possible. In areas where community-acquired MRSA isolates are prevalent, uncomplicated SSTI in healthy individuals may be treated empirically with clindamycin, trimethoprim-sulfamethoxazole, or long-acting tetracyclines, although specific data supporting the efficacy of these treatments are lacking. In healthy patients with small purulent lesions, drainage alone may be sufficient. In patients with complicated SSTI requiring hospitalization or intravenous therapy, vancomycin is the drug of choice because of the low cost, efficacy, and safety. Linezolid, daptomycin, and tigecycline are also effective, although published studies on the last 2 agents for the treatment of SSTI due to MRSA are more limited. Dalbavancin, telavancin, and ceftobiprole are investigational agents that may expand our therapeutic options for the treatment of SSTI caused by MRSA.

Methicillin-resistant Staphylococcus aureus (MRSA) continues to be an important pathogen worldwide, with high prevalence of infection in both community and hospital settings. Timely and appropriate choice of empirical therapy in the setting of MRSA infection is imperative due to the high rate of associated morbidity and mortality with MRSA infections. Initial choices should be made based on the site and severity of the infection, most notably moderate skin and soft tissue infections which may be treated with oral antibiotics (trimethoprim-sulfamethoxazole, clindamycin, doxycycline/minocycline, linezolid) in the outpatient setting, versus choice of parenteral therapy in the inpatient setting of more invasive or severe disease. Though the current recommendations continue to strongly rely on vancomycin as a standard empiric choice in the setting of severe/invasive infections, alternative therapies exist with studies supporting their non-inferiority. This includes the use of linezolid in pneumonia and severe skin and skin structure infections (SSSI) and daptomycin for MRSA bacteremia, endocarditis, SSSIs and bone/joint infections. Additionally, concerns continue to arise in regards to vancomycin, such as increasing isolate MICs, and relatively high rates of clinical failures with vancomycin. Thus, the growing interest in vanomycin alternatives, such as ceftaroline, ceftobribole, dalbavancin, oritavancin, and tedizolid, and their potential role in treating MRSA infections.