Investigation of vancomycin resistance in staphylococcus strains isolated from various clinical samples

Abstract

Introduction: Besides the few investigation demonstrating the vancomycin resistance towards Staphylococcus aureus in recent years, it has been also reported a decreased sensitivity of these bacteria to vancomycin. In the present study, it was aimed to evaluate sensitivity test in staphylococcus strains isolated from various clinical samples.Methods: A total of 164 staphylococcus strains consisting of Methicillin Resistant Staphylococcus aureus (n=93), and Methicillin Resistant Coagulase Negative Staphylococcus (n=71) were included in this study. The vancomycin agar screening and E-test methods were used to assess vancomycin sensitivity, and results were interpreted to Clinical and Laboratory Standard Institute and European Committee on Antimicrobial Susceptibility Testing criteria.Results: After assessing the strains by using E-Test, neither decreased sensitivity, nor resistance to vancomycin was determined according to Clinical and Laboratory Standard Institute. However, 3 of 6 Methicillin Resistant Staphylococcus aureus, and 1 of 7 Methicillin Resistant Coagulase Negative Staphylococcus reproduced in Brain Heart Infusion Agar were found to be resistant to vancomycin according to European Committee on Antimicrobial Susceptibility Testing.Conclusion: Because even small changes can be clinically significant, Minimum İnhibition Concentration value of vancomycin should be correctly determined.

Keywords

• stafilokok
• vankomisin
• antibiyotik direnc
• staphylococcus
• vancomycin
• antibiotic resistance