[Bacterial growth delay in E. coli: demonstration and evaluation of the beta-lactamase post-inhibitor effect on 6 strains with different resistance phenotypes].
Six E. coli, whose phenotypes of resistance were different, were tested in vitro in order to evaluate a regrowth delay, the post beta-lactamases inhibitor effect (PLIE). This PLIE was investigated after a brief incubation in contact with clavulanic acid (CA) alone or associated with amoxicillin (AMX). After removal of the drugs used during the pre-exposure phase, the bacteria were incubated with AMX at different concentrations. The PLIE was shown not to be in association with any other regrowth delay (post-antibiotic effect or effect inherent to the technical procedures used). A PLIE was evaluated on the five intermediary or high-level beta-lactamases-producing strains. Generally, the duration of the PLIE was prolonged after the CA alone pre-exposure phase and could reach values up to 22 hours. The concentrations of AMX added in cultures previously exposed to sufficient CA concentrations were related to an extended PLIE.
Murbach
V
V
Laboratoire d'antibiologie, faculté de médecine, hôpitaux universitaires de Strasbourg, France.
Bronner
S
S
Dhoyen
N
N
Sougakoff
W
W
Monteil
H
H
Jehl
F
F
D000658:Amoxicillin / Q000494:pharmacology; D019818:Clavulanic Acid / Q000494:pharmacology; D004352:Drug Resistance, Microbial; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development*; D010405:Penicillinase / Q000096:biosynthesis; D010406:Penicillins / Q000494:pharmacology; D010641:Phenotype; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000096:biosynthesis
D004791:Enzyme Inhibitors; D010406:Penicillins; D065093:beta-Lactamase Inhibitors; D019818:Clavulanic Acid; D000658:Amoxicillin; D010405:Penicillinase; D001618:beta-Lactamases