Evaluation of temocillin for phenotypic carbapenemase screening of Escherichia coli and Salmonella enterica isolates in relation to the presence of genes encoding ESBLs and carbapenemase production.
J Antimicrob Chemother
; 74(3): 639-644, 2019 03 01.
Article
en En
| MEDLINE
| ID: mdl-30544192
BACKGROUND: The expression of enzymes of the OXA-48 carbapenemase group is difficult to detect by phenotypic methods owing to frequent low levels of carbapenem resistance and negative results with some screening methods. Temocillin has been shown to be a good option for phenotypic screening as it is hydrolysed by the OXA-48-group enzymes, whereas ESBLs, AmpC and some other carbapenemases have a lower hydrolytic effect on this antimicrobial. However, no epidemiological cut-off for temocillin is available. OBJECTIVES: To evaluate temocillin MICs in relation to the presence or absence of genes encoding ESBLs and carbapenemases in Escherichia coli and Salmonella enterica. METHODS: In this study, 111 E. coli and 102 S. enterica isolates, including WT and well-characterized ESBL-, AmpC- or carbapenemase-producing isolates, were tested by three independent laboratories. MICs were determined according to the CLSI guidelines by agar dilution with the test range from 0.5 to 512 mg/L temocillin and WGS was performed and analysed with ResFinder. RESULTS: Some overlap was detected between temocillin MICs for WT and ESBL- or AmpC-producing isolates. However, isolates carrying genes encoding carbapenemases showed a broader range of MICs for both E. coli and S. enterica. Higher MICs were observed for the OXA-48 group, VIM and some NDM-producing isolates, whereas isolates harbouring KPC enzymes showed low MICs. CONCLUSIONS: The results indicate that temocillin MICs enable phenotypic distinction between strains producing OXA-48-group enzymes and both WT susceptible and ESBL/AmpC-carrying isolates, whereas the distinction from other carbapenemases likely requires genotypic testing.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Penicilinas
/
Proteínas Bacterianas
/
Beta-Lactamasas
/
Tamizaje Masivo
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Técnicas Bacteriológicas
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Salmonella enterica
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Escherichia coli
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Antibacterianos
Tipo de estudio:
Diagnostic_studies
/
Screening_studies
Idioma:
En
Revista:
J Antimicrob Chemother
Año:
2019
Tipo del documento:
Article
País de afiliación:
Dinamarca
Pais de publicación:
Reino Unido