Clinical isolates of Escherichia coli solely resistant to mecillinam: prevalence and epidemiology.
Int J Antimicrob Agents
; 51(3): 493-497, 2018 Mar.
Article
em En
| MEDLINE
| ID: mdl-29154843
ABSTRACT
In routine susceptibility testing of Gram-negative bacteria, a particular resistance phenotype was observed an Escherichia coli isolate from a urine sample exhibited resistance solely to mecillinam (MEC) but was fully susceptible to other ß-lactam antibiotics (MEC-R-BL-S). The objectives as this study were to determine the prevalence of this phenotype and to describe the phenotype, molecular epidemiology and genetic background. Between 1 January 2014 and 31 January 2016, MEC-R-BL-S E. coli isolates from urine were collected and genes previously reported as mostly involved in MEC resistance were analysed. The genetic relatedness among isolates was investigated by repetitive element sequence-based PCR (rep-PCR) and multilocus sequence typing (MLST). Ten MEC-R-BL-S isolates were collected, accounting for 0.4% (10/2547) of all E. coli obtained from urine samples, 0.9% (10/1135) of ampicillin-susceptible E. coli isolates and 9.6% (10/104) of MEC-R E. coli isolates. The isolates appeared as small colonies with round morphology and had impaired fitness. The isolates were not clonal and belonged to various extraintestinal or commensal E. coli phylogroups. Mutations in the cysB gene were evidenced in all clinical isolates. In conclusion, microbiologists should be aware of these isolates with a particular susceptibility phenotype, which is not due to error in disk diffusion but is a real non-enzymatic antibiotic resistance pattern.
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Base de dados:
MEDLINE
Assunto principal:
Infecções Urinárias
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Resistência beta-Lactâmica
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Escherichia coli
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Infecções por Escherichia coli
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Andinocilina
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Anti-Infecciosos Urinários
Tipo de estudo:
Prevalence_studies
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Risk_factors_studies
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Screening_studies
Limite:
Adult
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Aged
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Aged80
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Female
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Humans
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Male
Idioma:
En
Revista:
Int J Antimicrob Agents
Ano de publicação:
2018
Tipo de documento:
Article