In vivo reversion to the wild-type beta-lactam resistance phenotype mediated by a plasmid carrying ampR and qnrA1 in Enterobacter cloacae.
نویسندگان
چکیده
Resistance to beta-lactams and quinolones in two isogenic Enterobacter cloacae isolates was studied. One was susceptible to cefoxitin and amoxicillin-clavulanate. The other one showed its natural beta-lactam resistance pattern. Both isolates had a nonfunctional AmpR regulator. However, within the second one, the presence of a plasmid carrying ampR and qnrA1 allowed reversion to the wild-type beta-lactam resistance phenotype and decreased susceptibility to fluoroquinolones.
منابع مشابه
Enterobacter cloacae Outbreak and Emergence of Quinolone Resistance Gene in Dutch Hospital
An outbreak of Enterobacter cloacae infections with variable susceptibility to fluoroquinolones occurred in the University Medical Center Utrecht in the Netherlands in 2002. Our investigation showed that a qnrA1 gene was present in 78 (94%) of 83 outbreak isolates and that a qnrA1-encoding plasmid transferred to other strains of the same species and other species. The earliest isolate carrying ...
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BACKGROUND We investigated the prevalence of plasmid-mediated quinolone resistance and its association with extended-spectrum beta-lactamase (ESBL) and AmpC beta-lactamase in Enterobacteriaceae. METHODS A total of 347 non-duplicated isolates of Enterobacteriaceae were collected between August and October 2006 from 2 hospitals. Qnr determinant screening was conducted using PCR amplification, a...
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ورودعنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 50 9 شماره
صفحات -
تاریخ انتشار 2006