Invasive MRSA is typically treated with vancomycin or daptomycin. Vancomycin is a glycopeptide that inhibits cell wall synthesis. Although this is usually the first choice, there is growing concern regarding emerging resistance to Vancomycin and tissue penetration is limited to bone, lung, and CSF. Daptomycin is a cyclic lipopeptide bactericidal antibiotic that ultimately causes depolarization of the bacterial cell membrane. It is most effective for complicated skin infections as well as bacteremia and/or endocarditis. It is not effective in the treatment of MRSA pneumonia because its action is inhibited by surfactant. An alternative option for treatment of resistant MRSA infection is Linezolid. Linezolid has high bioavailability when administered parenterally or orally. It can be used for the treatment of nosocomial pneumonia and complicated skin infections.
Defined by: Jim Deering, MD