Quinupristin–dalfopristin versus linezolid for the treatment of vancomycin-resistant Enterococcus faecium bacteraemia: Efficacy and development of resistance

Abstract

Quinupristin–dalfopristin and linezolid are widely used for the treatment of vancomycin-resistant Enterococcus faecium (VREF) infections. Increasing resistance of VREF to quinupristin–dalfopristin and linezolid is a cause for concern. To determine the efficacy of and the rate of development of resistance to quinupristin–dalfopristin and linezolid, we analyzed all episodes of clinically significant VREF bacteraemia at a tertiary-care hospital from January 2003 to June 2007. The main outcomes were rates of 30-day mortality, microbiological response, and development of resistance. Fifty-two patients were treated with quinupristin–dalfopristin and 61 were treated with linezolid. Baseline demographic and clinical characteristics were similar between the 2 groups. There were no significant between-group differences in 30-day mortality (48% in the quinupristin–dalfopristin group vs 41% in the linezolid group; p = 0.45) or microbiological response (60% vs 66%; p = 0.51). However, prolonged bacteraemia (18% of 45 evaluable cases vs 4% of 55 evaluable cases; p = 0.04) and development of resistance in blood isolates (11% vs 0%; p = 0.02) were more frequently observed in the quinupristin–dalfopristin group than in the linezolid group. There was no significant difference between the efficacy of quinupristin–dalfopristin and linezolid. However, prolonged bacteraemia and the development of resistance were more common in quinupristin–dalfop ristin-treated patients.

Acknowledgements

This research was supported by a Bio R&D program through the National Research Foundation of Korea, which is funded by the Ministry of Education, Science and Technology (grant nos 2009-0091639 and 2009-0091640). This work was presented in part at the 48th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) and the 46th Annual Meeting of the Infectious Diseases Society of America (IDSA), Washington DC, 2008

Declaration of interest: All authors declare that they have no conflicts of interest regarding this work. The authors alone are responsible for the content and writing of the paper.