Activities of imipenem and cephalosporins against clonally related strains of Escherichia coli hyperproducing chromosomal beta-lactamase and showing altered porin profiles.
نویسندگان
چکیده
Forty clonally related clinical isolates of Escherichia coli from hospitalized patients were resistant to cefoxitin (MICs, >256 microg/ml) and ceftazidime (MICs, 32 to 256 microg/ml) and were intermediate or resistant to cefotaxime (MICs, 16 to 128 microg/ml) but susceptible to both cefepime (MICs, 0.5 to 2 microg/ml) and imipenem (MICs, 0.125 to 0.25 microg/ml). Resistance to beta-lactams was related to high-level production of AmpC beta-lactamase and loss of OmpF porin.
منابع مشابه
Prevalence and molecular characterization of clinical isolates of Escherichia coli expressing an AmpC phenotype.
OBJECTIVES To establish the prevalence of the AmpC beta-lactamase phenotype in clinical isolates of Escherichia coli and characterize the genetic resistance mechanisms causing the observed phenotype. METHODS Clinical E. coli (n = 74) with reduced susceptibility to third-generation cephalosporins and resistance to cefoxitin were collected from the Department of Clinical Microbiology at Hvidovr...
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ورودعنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 44 9 شماره
صفحات -
تاریخ انتشار 2000