title: Postantibiotic and bactericidal effect of imipenem against Pseudomonas aeruginosa.
abstract: The postantibiotic effect of imipenem on Pseudomonas aeruginosa was studied at different inocula using one ATCC strain and four clinical isolates. The postantibiotic effect was measured using two different methods: viable counts and bioluminescence assay of intracellular bacterial ATP. The postantibiotic effect could be demonstrated with both methods (viable counts 1-2 h, ATP assay 3-5 h) for all strains at an inoculum of 10(6) CFU/ml. When the inoculum was raised to 10(8) CFU/ml, no postantibiotic effect could be observed with either method using routine growth conditions. This disappearance of the postantibiotic effect coincided with a loss of bactericidal effect of imipenem when high inocula were used. Improved oxygenation of the cultures restored the bactericidal and postantibiotic effects of imipenem at high inocula.
authors.affiliation: Department of Infectious Diseases, Uppsala University, Sweden.
authors.forename: I
authors.initials: I
authors.lastname: Odenholt
authors.forename: B
authors.initials: B
authors.lastname: Isaksson
authors.forename: L
authors.initials: L
authors.lastname: Nilsson
authors.forename: O
authors.initials: O
authors.lastname: Cars
mesh_terms: D004305:Dose-Response Relationship, Drug; D006801:Humans; D015378:Imipenem / Q000008:administration & dosage / Q000032:analysis / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000254:growth & development
chemical_list: D015378:Imipenem