title: Efficacy of telithromycin (HMR 3647) against enterococci in a mouse peritonitis model.
abstract: We used a mouse peritonitis model to evaluate the in vivo efficacy of telithromycin (HMR 3647) (TEL) and erythromycin (ERY) against four strains of Enterococcus faecalis and three strains of Enterococcus faecium with differing susceptibilities to TEL. TEL was highly active in vivo against Ery-susceptible (Ery(s)) and -intermediate (Ery(i)) strains (MIC of TEL = 0.015 to 0.062 microg/ml) and showed less efficacy against Ery-resistant (Ery(r)) isolates (MIC of TEL = 4 to 16 microg/ml), although this was overcome in part by a second subcutaneous dose. Quinupristin-dalfopristin was also noted to have less efficacy against Ery(r) versus Ery(s) or Ery(i) E. faecium strains, but this difference was reduced by intravenous administration. In conclusion, TEL was more potent in vivo against enterococci than was ERY; its activity was lowered by the presence of erm(B)-mediated Ery(r).
authors.affiliation: Center for the Study of Emerging and Re-Emerging Pathogens, The University of Texas Medical School, Houston, Texas 77030, USA. Kavindra.Singh@uth.tmc.edu
authors.forename: K V
authors.initials: KV
authors.lastname: Singh
authors.forename: K K
authors.initials: KK
authors.lastname: Zscheck
authors.forename: B E
authors.initials: BE
authors.lastname: Murray
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004352:Drug Resistance, Microbial; D016983:Enterococcus / Q000187:drug effects; D004917:Erythromycin / Q000494:pharmacology; D048628:Ketolides; D018942:Macrolides; D051379:Mice; D008826:Microbial Sensitivity Tests; D010538:Peritonitis / Q000517:prevention & control*
chemical_list: D000900:Anti-Bacterial Agents; D048628:Ketolides; D018942:Macrolides; D004917:Erythromycin; C106791:telithromycin