OBJECTIVES Ciprofloxacin is the most frequently used member of the fluoroquinolones during initial eradication therapy of Pseudomonas aeruginosa, as well as during acute pulmonary exacerbations. However, its long-term effect on the susceptibility of the commensal flora within the cystic fibrosis (CF) airways has not yet been examined. The aim of this study was therefore to examine the consequen...

BACKGROUND & OBJECTIVES Diverse mechanisms have been identified in enteric bacteria for their adaptation and survival against multiple classes of antimicrobial agents. Resistance of bacteria to the most effective fluoroquinolones have increasingly been reported in many countries. We have identified that most of the enterotoxigenic Escherichia coli (ETEC) were resistant to several antimicrobials...

Sir, In Gram-positive cocci, fluoroquinolone resistance is associated with mutational alterations in DNA gyrase and/or topoisomerase IV or with active efflux of the drugs. In Streptococcus pneumoniae, fluoroquinolone resistance is mainly due to substitutions in ParC (Ser-79→Phe or Tyr, Asp-83→Asn), ParE (Asp-435→Asn) or GyrA (Ser-81→Phe or Tyr, Glu-85→Lys or Gly).1,2 Therefore, detection of the...

Background: Quinolone resistant Salmonella serotypes have been reported in recent years and become increasingly widespread worldwide. Objectives: We evaluated the molecular mechanism of quinolone resistance non-typhoidal strains isolated from clinical samples Tehran, Iran. Methods: The present study included isolates originated hospitalized individuals outpatients Serotyping nalidixic acid-resi...

The ability of Mycoplasma synoviae, an avian pathogen, to persist despite fluoroquinolone treatments was investigated in hens. Groups of Mycoplasma-free hens were experimentally infected with the M. synoviae 317 strain and treated twice with enrofloxacin at the therapeutic dose. The results show that the two treatments did not have any influence on this strain of M. synoviae recovery from trach...

BACKGROUND Quinolone resistance in Enterobacteriaceae species has increased over the past few years, and is significantly associated to beta-lactam resistance. The aim of this study was to evaluate the prevalence of chromosomal- and plasmid-mediated quinolone resistance in acquired AmpC β-lactamase and/or carbapenemase-producing Enterobacteriaceae isolates. METHODS The presence of chromosomal...

Mutations in quinolone targets were studied together with quinolone efflux pump activation and plasmid-mediated quinolone resistance determinants in nalidixic-acid-resistant isolates of Aeromonas caviae and Aeromonas veronii. Among 135 clinical Aeromonas spp. isolated from stools of patients with gastrointestinal symptoms, 40 nalidixic acid-resistant strains belonging to A. caviae and A. veroni...

BACKGROUND Antimicrobial resistance of Streptococcus agalactiae (Group B Streptococcus, GBS) has been emerging worldwide. We aimed to examine the correlation of drug-resistant genes with serotypes and with the mutations of the quinolone resistance-determining region (QRDR) in GBS isolates. METHODS A total of 323 human GBS isolates were collected from a hospital in southern Taiwan. Laboratory ...