Bactericidal activity of oxacillin and glycopeptides against Staphylococcus aureus in patients with endocarditis: Looking for a relationship between tolerance and outcome

Annals of Clinical Microbiology and Antimicrobials

Research

Laura Soavi¹  Veronica Ravasio¹  Amedeo Moretti²  Maria Bruna Pasticci²  Carlo Pallotto²  Alessio Sgrelli²  Franco Baldelli²  Giuliano Stagni²  Angela Cardaccia²  Antonella Santucci²  Rita Papili²  Francesca Vailati³  Annibale Raglio³ 

[1]Infectious Disease Department, Ospedali Riuniti di Bergamo, Bergamo, Italy

[2]Section of Infectious Diseases, Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy

[3]Unit of Microbiology and Virology, Ospedali Riuniti di Bergamo, Bergamo, Italy

关键词: Bactericidal Activity;    Vancomycin;    Endocarditis;    Glycopeptide;    Teicoplanin;   

DOI  :  10.1186/1476-0711-10-26

 received in 2011-01-26, accepted in 2011-06-09,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundThere is no clear relationship between in vitro bactericidal activity tests and clinical outcome. We studied bactericidal activity of oxacillin, vancomycin and teicoplanin against Staphylococcus aureus isolates in patients with endocarditis and then we sought to determine if there was a relationship between in vitro bactericidal activity and clinical outcome.MethodsMinimal bacteriostatic and minimal bactericidal concentrations were determined for Staphylococcus aureus strains isolated from patients with endocarditis following standardized methods. Medical records were reviewed retrospectively to collect data on antimicrobial susceptibility at admission, antimicrobial therapy, need for surgery, embolic events and outcome.Results and DiscussionSixty-two Staphylococcus aureus strains were studied in 62 patients with endocarditis. Overall, 91.9% definite, 21% methicillin resistant and 72.6% cured. Surgery was performed in 32.3% and embolic events were documented in 64.5%. Tolerance to oxacillin and teicoplanin was more common than vancomycin tolerance among methicillin susceptible Staphylococcus aureus. Among methicillin resistant Staphylococcus aureus teicoplanin was shown to have a higher rate of tolerance than vancomycin. No statistically significant differences on clinical outcome between oxacillin tolerant and oxacillin non tolerant Staphylococcus aureus infections were observed. Tolerance to oxacillin did not adversely affect clinical outcomes of patients with methicillin susceptible Staphylococcus aureus endocarditis treated with a combination of antimicrobials including oxacillin. The cure rate was significantly lower among patients with methicillin resistant Staphylococcus aureus endocarditis.ConclusionsIn vitro bactericidal test results were not valid predictors of clinical outcome. Physicians need to use additional parameters when treating patients with staphylococcal endocarditis.

【 授权许可】

CC BY   
© Pasticci et al; licensee BioMed Central Ltd. 2011