İnvestigation of Daptomycin Sensitivities in Methicillin Resistant Staphylococcus Aureus and Vancomycin Resistant Enterococcal Strains by İn Vitro E-Test Method

Abstract

INTRODUCTION: The antibiotic resistance problem in the world has emerged as multiple antibiotic resistance in recent years. Despite the limited options in the treatment of infections, the inability of producing new antibiotics also keeps the problem current. In our study, it was aimed to investigate daptomycin susceptibility, which is an important option in the treatment of MRSA and VRE infections. METHODS: 81 MRSA and 11 VRE strains were included in our study that isolated from various specimens between October 2011 and June 2013. The susceptibility of these strains to daptomycin was determined by the E-test method with CLSI recommendations. RESULTS: The susceptibility of S. aureus strains to daptomycin and linezolid was 100%. On the other hand it was over 90% in vancomycin, teicoplanin, nitrofurantoin, quinupristin-dalfopristin and trimethoprim-sulfamethoxazole. Also we found lower rates in tetracycline (22%), norfloxacin (21%) and gentamicin (25%). Enterococcus were 100% susceptible to daptomycin and 82% to linezolid, while 100% resistant to ampicillin, penicillin, erythromycin, nitrofurantoin, rifampin, and teicoplanin. DISCUSSION AND CONCLUSION: Daptomycin may be as an alternative agent in MRSA and VRE infections. Although it is effective in gram positives, resistance is increasing. There is a need for new agents which are more effective and have appropriate pharmacokinetic and safety profiles.

Keywords

• daptomycin sensitivity
• e-test
• methicillin-resistant staphylococcus aureus
• vancomycin-resistant enterococcus