In vitro activity of linezolid against multiply resistant Gram-positive clinical isolates

The in vitro activity of the oxazolidinone linezolid was compared with the activities of vancomycin and telcoplanin against 450 Gram-positive clinical isolates, including a variety of multiply resistant strains. Linezolid inh ibited all microorganisms tested at less than or equal to4 mg/L, including methicillin- and teicoplanin-resistant staphylococci, glycopeptide-resistan t enterococci, penicillin- and multiply resistant pneumococci and viridans streptococci, and erythromycin-resistant beta -haemolytic streptococci. The MIC90 of linezolid for all isolates was 2 mg/L.