Antibiotic choice may not explain poorer outcomes in patients with Staphylococcus aureus bacteremia and high Vancomycin minimum inhibitory concentrations

Date

2011

Authors

Holmes, N.
Turnidge, J.
Munckhof, W.
Robinson, J.
Korman, T.
O'Sullivan, M.
Anderson, T.
Roberts, S.
Gao, W.
Christiansen, K.

Editors

Advisors

Journal Title

Journal ISSN

Volume Title

Type:

Journal article

Citation

Journal of Infectious Diseases, 2011; 204(3):340-347

Statement of Responsibility

Natasha E. Holmes, John D. Turnidge, Wendy J. Munckhof, James O. Robinson, Tony M. Korman, Matthew V. N. O'Sullivan, Tara L. Anderson, Sally A. Roberts, Wei Gao, Keryn J. Christiansen, Geoffrey W. Coombs, Paul D. R. Johnson and Benjamin P. Howden

Conference Name

Abstract

Background. There are concerns about reduced efficacy of vancomycin in patients with Staphylococcus aureus bacteremia (SAB), especially when the minimum inhibitory concentration (MIC) nears the upper limit of the susceptible range. Methods. We examined the relationship between antibiotic treatment, 30-day mortality, and microbiologic parameters in a large Australasian cohort of patients with SAB. Results. We assessed 532 patients with SAB from 8 hospitals. All patients with methicillin-resistant S. aureus (MRSA) bacteremia were treated with vancomycin, and patients with methicillin-susceptible S. aureus (MSSA) bacteremia received either flucloxacillin or vancomycin. Increasing vancomycin MIC was associated with increased mortality in vancomycin-treated patients. However, even in patients with MSSA bacteremia treated with flucloxacillin, mortality was also higher if the vancomycin Etest MIC of their isolate was >1.5 μg/mL, compared with those with lower MIC isolates (26.8% vs 12.2%; P < .001). After adjustment in a multivariate model, age, hospital-onset SAB and vancomycin MIC were independently associated with mortality, but methicillin resistance and antibiotic choice were not. Conclusions. We have confirmed an association between higher vancomycin MIC and increased mortality in patients with SAB, but surprisingly this relationship was not related to the antibiotic treatment received, suggesting that the use of vancomycin per se is not responsible for the poorer outcome.

School/Discipline

Dissertation Note

Provenance

Description

Access Status

Rights

© The Author 2011. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved.

License

Grant ID

Call number

Persistent link to this record