[Evaluation of vancomycin, teicoplanin, linezolide and tigecycline susceptibilities of nosocomial methicillin-resistant Staphylococcus strains by E-test].

The aim of this study was to determine the minimal inhibitory concentration (MIC) values of vancomycin, teicoplanin, tigecycline and linezolid in 100 methicillin-resistant staphylococci [21 methicillin-resistant Staphylococcus aureus (MRSA) and 79 methicillin-resistant coagulase negative staphylococcus (MR-CNS)] isolated as agents of nosocomial infection from patients at Ankara Training and Research Hospital between June 2005-March 2007. The MIC values for vancomycin, teicoplanin, linezolid and tigecycline were tested by E-test method (AB Biodisk, Sweden). For 21 MRSA strains MIC50 and MIC90 values were as follows: vancomycin 0.125 µg/ml and 1 µg/ml; teicoplanin 0.5 µg/ml and 3 µg/ml, linezolid 0.047 µg/ml and 0.19 µg/ml; tigecycline 0.094 µg/ml and 0.5 µg/ml, respectively. For 79 MR-CNS strains MIC50 and MIC90 values were as follows: vancomycin 0.5 µg/ml and 2 µg/ml; teicoplanin 2 µg/ml and 4 µg/ml; linezolid 0.125 µg/ml and 0.25 µg/ml; tigecycline 0.38 µg/ml and 0.5 µg/ml, respectively. No resistance to vancomycin, teicoplanin, tigecycline and linezolid were determined in methicillin-resistant staphylococcus strains isolated from the inpatients in our hospital. Among glycopeptides, MIC50 and MIC90 values of vancomycin were found to be lower than that of teicoplanin.