title: Comparative in vitro and in vivo efficacy of roxithromycin and erythromycin against a strain of methicillin-susceptible Staphylococcus epidermidis.
abstract: The in vitro and in vivo efficacy of roxithromycin was compared with that of erythromycin, against a methicillin-susceptible strain of Staphylococcus epidermidis. We performed standard in vitro testing (MIC, MBC, and time-kill kinetics) for roxithromycin, erythromycin, and rifampin. Both macrolides were bacteriostatic in vitro. There was no significant difference in microbial survival between erythromycin and roxithromycin groups in the time-kill kinetics (p = 0.3). For the in vivo experiments, using the rabbit experimental endocarditis model, roxithromycin was found to be inferior to erythromycin in decreasing the microbial burden of the endocardial vegetations (p < 0.05). Rifampin was highly effective, both in vitro and in vivo. In conclusion, the efficacy of roxithromycin was poor and inferior to erythromycin against a strain of methicillin-susceptible S. epidermidis.
authors.affiliation: University of Athens Medical School, Second Department of Internal Medicine-Propaedeutic, Greece.
authors.forename: P G
authors.initials: PG
authors.lastname: Danias
authors.forename: G
authors.initials: G
authors.lastname: Chalevelakis
authors.forename: E E
authors.initials: EE
authors.lastname: Mylonakis
authors.forename: A
authors.initials: A
authors.lastname: Argyropoulou
authors.forename: O
authors.initials: O
authors.lastname: Paniara
authors.forename: G
authors.initials: G
authors.lastname: Saroglou
authors.forename: S A
authors.initials: SA
authors.lastname: Raptis
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D004195:Disease Models, Animal; D004352:Drug Resistance, Microbial; D004697:Endocarditis, Bacterial / Q000188:drug therapy* / Q000382:microbiology; D004917:Erythromycin / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D008712:Methicillin / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D010406:Penicillins / Q000494:pharmacology; D011817:Rabbits; D015575:Roxithromycin / Q000494:pharmacology* / Q000627:therapeutic use; D012680:Sensitivity and Specificity; D013203:Staphylococcal Infections / Q000188:drug therapy* / Q000382:microbiology; D013212:Staphylococcus epidermidis / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D010406:Penicillins; D015575:Roxithromycin; D004917:Erythromycin; D008712:Methicillin