Previous Article | Next Article 
Antimicrobial Agents and Chemotherapy, January 2005, p. 45-51, Vol. 49, No. 1
0066-4804/05/$08.00+0 doi:10.1128/AAC.49.1.45-51.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.
In Vitro and In Vivo Synergistic Activities of Linezolid Combined with Subinhibitory Concentrations of Imipenem against Methicillin-Resistant Staphylococcus aureus
Cédric Jacqueline,
Dominique Navas,
Eric Batard,
Anne-Françoise Miegeville,
Virginie Le Mabecque,
Marie-France Kergueris,
Denis Bugnon,
Gilles Potel, and
Jocelyne Caillon*
Laboratoire d'Antibiologie (UPRES EA 3826), UER de Médecine, Nantes, France
Received 26 July 2004/
Returned for modification 3 September 2004/
Accepted 27 September 2004
Indifference or moderate antagonism of linezolid combined with other antibiotics in vitro and in vivo have mainly been reported in the literature. We have assessed the in vitro activities of linezolid, alone or in combination with imipenem, against methicillin-resistant Staphylococcus aureus (MRSA) strains using the dynamic checkerboard and time-kill curve methods. Linezolid and low concentrations of imipenem had a synergistic effect, leading us to evaluate the in vivo antibacterial activity of the combination using the rabbit endocarditis experimental model. Two MRSA strains were used for in vivo experiments: one was a heterogeneous glycopeptide-intermediate clinical S. aureus strain isolated from blood cultures, and the other was the S. aureus COL reference strain. Animals infected with one of two MRSA strains were randomly assigned to one of the following treatments: no treatment (controls), linezolid (simulating a dose in humans of 10 mg/kg of body weight every 12 h), a constant intravenous infusion of imipenem (which allowed the steady-state concentration of about 1/32 the MIC of imipenem for each strain to be reached in serum), or the combination of both treatments. Linezolid and imipenem as monotherapies exhibited no bactericidal activity against either strain. The combination of linezolid plus imipenem showed in vivo bactericidal activity that corresponded to a decrease of at least 4.5 log CFU/g of vegetation compared to the counts for the controls. In conclusion, the combination exhibited synergistic and bactericidal activities against two MRSA strains after 5 days of treatment. The combination of linezolid plus imipenem appears to be promising for the treatment of severe MRSA infections and merits further investigations to explore the mechanism underlying the synergy between the two drugs.
* Corresponding author. Mailing address: Laboratoire d'Antibiologie (UPRES EA 3826), UER de Médecine, 1 rue Gaston Veil, 44035 Nantes, Cedex 01, France. Phone and Fax: (33) 240-41-2854. E-mail:
jcaillon{at}sante.univ-nantes.fr.
Antimicrobial Agents and Chemotherapy, January 2005, p. 45-51, Vol. 49, No. 1
0066-4804/05/$08.00+0 doi:10.1128/AAC.49.1.45-51.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Nguyen, H. M., Graber, C. J.
(2009). Limitations of antibiotic options for invasive infections caused by methicillin-resistant Staphylococcus aureus: is combination therapy the answer?. J Antimicrob Chemother
0: dkp377v1-dkp377
[Abstract]
[Full Text]
-
Endorsed by the European Society of Clinical Micro, , Authors/Task Force Members, , Habib, G., Hoen, B., Tornos, P., Thuny, F., Prendergast, B., Vilacosta, I., Moreillon, P., de Jesus Antunes, M., Thilen, U., Lekakis, J., Lengyel, M., Muller, L., Naber, C. K., Nihoyannopoulos, P., Moritz, A., Zamorano, J. L., ESC Committee for Practice Guidelines (CPG), , Vahanian, A., Auricchio, A., Bax, J., Ceconi, C., Dean, V., Filippatos, G., Funck-Brentano, C., Hobbs, R., Kearney, P., McDonagh, T., McGregor, K., Popescu, B. A., Reiner, Z., Sechtem, U., Sirnes, P. A., Tendera, M., Vardas, P., Widimsky, P., Document Reviewers, , Vahanian, A., Aguilar, R., Bongiorni, M. G., Borger, M., Butchart, E., Danchin, N., Delahaye, F., Erbel, R., Franzen, D., Gould, K., Hall, R., Hassager, C., Kjeldsen, K., McManus, R., Miro, J. M., Mokracek, A., Rosenhek, R., San Roman Calvar, J. A., Seferovic, P., Selton-Suty, C., Uva, M. S., Trinchero, R., van Camp, G.
(2009). Guidelines on the prevention, diagnosis, and treatment of infective endocarditis (new version 2009): The Task Force on the Prevention, Diagnosis, and Treatment of Infective Endocarditis of the European Society of Cardiology (ESC). Eur Heart J
30: 2369-2413
[Full Text]
-
Jacqueline, C., Caillon, J., Le Mabecque, V., Miegeville, A.-F., Hamel, A., Bugnon, D., Ge, J. Y., Potel, G.
(2007). In Vivo Efficacy of Ceftaroline (PPI-0903), a New Broad-Spectrum Cephalosporin, Compared with Linezolid and Vancomycin against Methicillin-Resistant and Vancomycin-Intermediate Staphylococcus aureus in a Rabbit Endocarditis Model. Antimicrob. Agents Chemother.
51: 3397-3400
[Abstract]
[Full Text]
-
Fox, P. M., Lampen, R. J., Stumpf, K. S., Archer, G. L., Climo, M. W.
(2006). Successful Therapy of Experimental Endocarditis Caused by Vancomycin-Resistant Staphylococcus aureus with a Combination of Vancomycin and {beta}-Lactam Antibiotics.. Antimicrob. Agents Chemother.
50: 2951-2956
[Abstract]
[Full Text]
-
Jacqueline, C., Caillon, J., Grossi, O., Le Mabecque, V., Miegeville, A.-F., Bugnon, D., Batard, E., Potel, G.
(2006). In Vitro and In Vivo Assessment of Linezolid Combined with Ertapenem: a Highly Synergistic Combination against Methicillin-Resistant Staphylococcus aureus.. Antimicrob. Agents Chemother.
50: 2547-2549
[Abstract]
[Full Text]
-
Petersen, P. J., Labthavikul, P., Jones, C. H., Bradford, P. A.
(2006). In vitro antibacterial activities of tigecycline in combination with other antimicrobial agents determined by chequerboard and time-kill kinetic analysis. J Antimicrob Chemother
57: 573-576
[Abstract]
[Full Text]
-
Jones, R. N., Ross, J. E., Fritsche, T. R., Sader, H. S.
(2006). Oxazolidinone susceptibility patterns in 2004: report from the Zyvox(R) Annual Appraisal of Potency and Spectrum (ZAAPS) Program assessing isolates from 16 nations. J Antimicrob Chemother
57: 279-287
[Abstract]
[Full Text]