This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Abgueguen, P.
Right arrow Articles by Bedos, J.-P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Abgueguen, P.
Right arrow Articles by Bedos, J.-P.

 Previous Article  |  Next Article 

Antimicrobial Agents and Chemotherapy, January 2007, p. 208-214, Vol. 51, No. 1
0066-4804/07/$08.00+0     doi:10.1128/AAC.00004-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Amoxicillin Is Effective against Penicillin-Resistant Streptococcus pneumoniae Strains in a Mouse Pneumonia Model Simulating Human Pharmacokinetics{triangledown}

Pierre Abgueguen,* Esther Azoulay-Dupuis, Violaine Noel, Pierre Moine, Veronique Rieux, Bruno Fantin, and Jean-Pierre Bedos

INSERM EMI-U 9933, Faculté de Médecine Xavier Bichat, Paris, France

Received 3 January 2006/ Returned for modification 13 February 2006/ Accepted 14 October 2006

High-dose oral amoxicillin (3 g/day) is the recommended empirical outpatient treatment of community-acquired pneumonia (CAP) in many European guidelines. To investigate the clinical efficacy of this treatment in CAP caused by Streptococcus pneumoniae strains with MICs of amoxicillin ≥2 µg/ml, we used a lethal bacteremic pneumonia model in leukopenic female Swiss mice with induced renal failure to replicate amoxicillin kinetics in humans given 1 g/8 h orally. Amoxicillin (15 mg/kg of body weight/8 h subcutaneously) was given for 3 days. We used four S. pneumoniae strains with differing amoxicillin susceptibility and tolerance profiles. Rapid bacterial killing occurred with an amoxicillin-susceptible nontolerant strain: after 4 h, blood cultures were negative and lung homogenate counts under the 2 log10 CFU/ml detection threshold (6.5 log10 CFU/ml in controls, P < 0.01). With an amoxicillin-intermediate nontolerant strain, significant pulmonary bacterial clearance was observed after 24 h (4.3 versus 7.9 log10 CFU/ml, P < 0.01), and counts were undetectable 12 h after treatment completion. With an amoxicillin-intermediate tolerant strain, 24-h bacterial clearance was similar (5.4 versus 8.3 log10 CFU/ml, P < 0.05), but 12 h after treatment completion, lung homogenates contained 3.3 log10 CFU/ml. Similar results were obtained with an amoxicillin-resistant and -tolerant strain. Day 10 survival rates were usually similar across strains. Amoxicillin with pharmacokinetics simulating 1 g/8 h orally in humans is bactericidal in mice with pneumonia due to S. pneumoniae for which MICs were 2 to 4 µg/ml. The killing rate depends not only on resistance but also on tolerance of the S. pneumoniae strains.


* Corresponding author. Mailing address: Service des Maladies Infectieuses et Tropicales, Centre Hospitalier Universitaire d'Angers, 4 rue Larrey, 49933 Angers Cedex 9, France. Phone: 33 241 453 930. Fax: 33 241 353 455. E-mail: piabgueguen{at}chu-angers.fr.

{triangledown} Published ahead of print on 23 October 2006.


Antimicrobial Agents and Chemotherapy, January 2007, p. 208-214, Vol. 51, No. 1
0066-4804/07/$08.00+0     doi:10.1128/AAC.00004-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:

  • Chiavolini, D., Pozzi, G., Ricci, S. (2008). Animal Models of Streptococcus pneumoniae Disease. Clin. Microbiol. Rev. 21: 666-685 [Abstract] [Full Text]