title: Efficacy of erythromycin lactobionate for treating Pseudomonas aeruginosa bacteremia in mice.
abstract: We induced endogenous Pseudomonas aeruginosa bacteremia by administering cyclophosphamide and ampicillin to specific pathogen-free mice fed P. aeruginosa. Using this model, we evaluated the efficacy of erythromycin lactobionate (EML) in treating P. aeruginosa bacteremia. Treatment with EML at 50 and 100 mg/kg of body weight per day twice a day for 14 days significantly increased the survival rate. The most effective dose was 100 mg/kg/day, with a survival rate of 80% compared with a 20% survival rate in the control. However, the administration of EML at 500 mg/kg/day rather decreased the survival rate. In a model of intravenous infection, treatment with EML at 100 mg/kg/day twice a day for 7 days before the bacterial challenge also enhanced the survival rate. EML levels in serum, liver, and stool were apparently lower than the MIC (512 micrograms/ml). These observations suggest that EML is effective against P. aeruginosa bacteremia despite a lack of specific activity for this pathogen. Although the protective mechanism is still unclear, it is possible that a subinhibitory level of EML may affect the virulence of P. aeruginosa and enhance the host defense system.
authors.affiliation: Department of Microbiology, Toho University School of Medicine, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hirakata
authors.forename: M
authors.initials: M
authors.lastname: Kaku
authors.forename: K
authors.initials: K
authors.lastname: Tomono
authors.forename: K
authors.initials: K
authors.lastname: Tateda
authors.forename: N
authors.initials: N
authors.lastname: Furuya
authors.forename: T
authors.initials: T
authors.lastname: Matsumoto
authors.forename: R
authors.initials: R
authors.lastname: Araki
authors.forename: K
authors.initials: K
authors.lastname: Yamaguchi
mesh_terms: D000818:Animals; D016470:Bacteremia / Q000188:drug therapy* / Q000382:microbiology; D004917:Erythromycin / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000627:therapeutic use; D005243:Feces / Q000737:chemistry; D008099:Liver / Q000378:metabolism; D051379:Mice; D008815:Mice, Inbred Strains; D008826:Microbial Sensitivity Tests; D011552:Pseudomonas Infections / Q000188:drug therapy* / Q000382:microbiology
chemical_list: C010948:erythromycin lactobionate; D004917:Erythromycin