High-Dose Vancomycin Therapy for Methicillin-Resistant Staphylococcus aureus Infections

Vancomycin hydrochloride treatment failure for infections caused by susceptible methicillin-resistant Staphylococcus aureus (MRSA) strains with high minimum inhibitory concentration (MIC) has prompted recent guidelines to recommend a higher vancomycin target trough of 15 to 20 microg/mL.

A prospective cohort study of adult patients infected with MRSA was performed to determine the distribution of vancomycin MIC and treatment outcomes with vancomycin doses targeting an unbound trough of at least 4 times the MIC. The microbiology laboratory computer records were used to identify all patients from whom MRSA was isolated from August 1, 2004, through June 30, 2005. Primary outcome measures were clinical response, mortality, and nephrotoxicity. Patients were placed into subgroups based on target trough attainment and high vs low vancomycin MIC (>/=2 vs /=15 vs