Mechanisms of resistance in nontyphoidal Salmonella enterica strains exhibiting a nonclassical quinolone resistance phenotype.

ABSTRACT: Nontyphoidal Salmonella enterica strains with a nonclassical quinolone resistance phenotype were isolated from patients returning from Thailand or Malaysia to Finland. A total of 10 isolates of seven serovars were studied in detail, all of which had reduced susceptibility (MIC > or = 0.125 microg/ml) to ciprofloxacin but were either susceptible or showed only low-level resistance (MIC < or = 32 microg/ml) to nalidixic acid. Phenotypic characterization included susceptibility testing by the agar dilution method and investigation of efflux activity. Genotypic characterization included the screening of mutations in the quinolone resistance-determining regions (QRDR) of gyrA, gyrB, parC, and parE by PCR and denaturing high-pressure liquid chromatography and the amplification of plasmid-mediate

SUBMITTER: Gunell M 

PROVIDER: S-EPMC2737843 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature