Abstract

Efficacies of cefotaxime and ceftriaxone in a mouse model of pneumonia induced by two penicillin- and cephalosporin-resistant strains of Streptococcus pneumoniae. C Sauve , E Azoulay-Dupuis , P Moine , C Darras-Joly , V Rieux , C Carbon and J P Bédos Institut National de la Santé et de la Recherche Medicale U 13, Groupe Hospitalier Bichat-Claude Bernard, Paris, France. ABSTRACT We previously demonstrated the efficacy of ceftriaxone (CRO), at 50 mg/kg of body weight every 12 h, against a highly penicillin-resistant (MIC, 4 micrograms/ml) Streptococcus pneumoniae strain with low-level resistance to CRO (MIC, 0.5 microgram/ml) in a leukopenic-mouse pneumonia model (P. Moine, E. Vallée, E. Azoulay-Dupuis, P. Bourget, J.-P. Bédos, J. Bauchet, and J.-J. Pocidalo, Antimicrob. Agents Chemother. 38:1953-1958, 1994). In the present study, we assessed the activity of CRO versus those of cefotaxime (CTX) and amoxicillin (AMO) against two highly penicillin- and cephalosporin-resistant S. pneumoniae strains (P40422 and P40984) (MICs of 2 and 8 for penicillin, 2 and 4 for AMO, and 4 and 8 for CRO or CTX, respectively). Against both strains, a greater than an 80% cumulative survival rate was observed with CRO at a dose of 100 or 200 mg/kg every 12 h (dose/MIC ratio, 25). With CTX, a high dosage of 400 mg/kg (dose/MIC ratio, 100 or 50) administered every 8 h (TID) was needed to protect 66 and 75% of the animals, respectively, with no statistically significant differences versus CRO. Against the P40422 strain, CRO (100 mg/kg) produced the greatest bactericidal effect, from the 8th to the 24th hour after a single injection (1.8-log-unit reduction over 24 h), and the fastest bacterial pulmonary clearance during treatment; with CTX, only multiple injections at a high dosage, i.e., 400 mg/kg TID, demonstrated a significant bactericidal effect. AMO in a high dosage, 400 mg/kg (dose/MIC ratio, 200) TID, showed good activity only against the P40422 strain. Despite the identical MICs of CTX and CRO, the longer time (3.6 to 4.6 h) that serum CRO concentrations remained above the MICs for the pathogens at a dose of 100 mg/kg resulted in greater efficacy versus CTX against highly penicillin- and cephalosporin-resistant S. pneumoniae strains. CiteULike Connotea Delicious Digg Facebook Google+ Mendeley Reddit StumbleUpon Twitter What's this? « Previous | Next Article » Table of Contents This Article Antimicrob. Agents Chemother. December 1996 vol. 40 no. 12 2829-2834 » Abstract PDF Services Email this article to a colleague Similar articles in ASM journals Alert me when this article is cited Alert me if a correction is posted Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of AAC Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Load citing article information Citing articles via Web of Science Citing articles via Google Scholar Google Scholar Articles by Sauve, C. Articles by Bédos, J. P. Search for related content PubMed PubMed citation Articles by Sauve, C. Articles by Bédos, J. P. Related Content Load related web page information Social Bookmarking CiteULike Connotea Delicious Digg Facebook Google+ Mendeley Reddit StumbleUpon Twitter What's this? current issue December 2011, volume 55, issue 12 Alert me to new issues of AAC About AAC Subscribers Authors Reviewers Advertisers Inquiries from the Press Permissions & Commercial Reprints ASM Journals Public Access Policy AAC RSS Feeds 1752 N Street N.W. • Washington DC 20036 202.737.3600 • 202.942.9355 fax • journals@asmusa.org Print ISSN: 0066-4804 Online ISSN: 1098-6596 Copyright © 2011 by the American Society for Microbiology. For an alternate route to AAC .asm.org, visit: http://intl- AAC .asm.org | More Info» var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www."); document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E")); var pageTracker = _gat._getTracker("UA-5821458-3"); pageTracker._trackPageview();