Objective:To investigate the mechanisms of quinolone resistance and the association with other resistance markers among Esherichia coli(E.coli) strains isolated from outpatient with urinary tract infection in north of...Objective:To investigate the mechanisms of quinolone resistance and the association with other resistance markers among Esherichia coli(E.coli) strains isolated from outpatient with urinary tract infection in north of Algeria.Methods:A total of 30 nalidixic acid-resistant E.coli isolates from outpatient with urinary tract infections from January 2010 to April 2011 in north of Algeria(Bejaia) were studied.Antimicrobial susceptibility was determined by disc diffusion assay,minimal inhibitory concentrations(MIC) of quinolone were determined by microdilution.Mutations in the Quinolone Resistance-Determining Region(QRDR) of gyra and parC genes and screening for qnr(A,B and S) and bla genes were done by PCK and UNA sequencing.Results:Most of the E.coli isolates(56.66%) were shown to carry mutations in gyrA and parC,igyra:Ser83Leu + Asp87Asn and parC:Ser80Iler.While.16.66 had only an alteration in gyrA:Ser83Leu.One isolate produced qnrB-like and two qnrS-like.Four isolates were CTXM-15 producers associated with TEM-1 producing in one case.Co-expression of bla_(LTV,M)_(15) and qnrB was determined in one E.coli isolate.Conclusions:Our findings suggested the community emergence of gyrA and parC alterations and Qnr determinants that contributed to the development and spread of fluoroquinolone resistance in Algerian E.coli isolates.展开更多
<b>Background:</b> Typhoid fever is a major public health concern in developing countries. The upsurge in the occurrence of bacterial isolates that are resistant to nalidixic acid;with reduced susceptibili...<b>Background:</b> Typhoid fever is a major public health concern in developing countries. The upsurge in the occurrence of bacterial isolates that are resistant to nalidixic acid;with reduced susceptibility to ciprofloxacin in typhoidal <i>Salmonellae</i> constitutes a challenge to the clinician. <b>Methods:</b> In order to better understand the epidemiology of <i>Salmonella</i> infections in South India, <i>Salmonella typhi</i> isolates were screened from various healthcare centers. <i>Salmonella</i> isolates were identified by using standard phenotypic, serological, antibiotic susceptibility and molecular methods. <b>Results:</b> Among a total of 100 <i>S. typhi</i> isolates 9% were found to be multidrug resistant and 30% were nalidixic acid resistant. Isolates with reduced susceptibility to ciprofloxacin displays single base mutations in the gyrA gene. A very low rate of 1% resistance was found to ciprofloxacin. The only one isolate with ciprofloxacin MIC ≥ 4 μg/ml also showed single mutation in the QRDR of the gyrA gene in <i>S. typhi</i> (GenBank accession no. HQ176349-HQ176368). <b>Conclusions:</b> A very low rate of nalidixic acid resistance with reduced susceptibility to ciprofloxacin was observed in comparison to other endemic areas in isolates of <i>S. typhi</i> from Gulbarga, South India, with steadily increasing NAR <i>S. typhi</i> but decreasing MDR isolations over the study period. This is most likely due to an increased use of ciprofloxacin as a first line drug of choice over more traditional antimicrobial agents for the treatment of typhoid fever.展开更多
文摘Objective:To investigate the mechanisms of quinolone resistance and the association with other resistance markers among Esherichia coli(E.coli) strains isolated from outpatient with urinary tract infection in north of Algeria.Methods:A total of 30 nalidixic acid-resistant E.coli isolates from outpatient with urinary tract infections from January 2010 to April 2011 in north of Algeria(Bejaia) were studied.Antimicrobial susceptibility was determined by disc diffusion assay,minimal inhibitory concentrations(MIC) of quinolone were determined by microdilution.Mutations in the Quinolone Resistance-Determining Region(QRDR) of gyra and parC genes and screening for qnr(A,B and S) and bla genes were done by PCK and UNA sequencing.Results:Most of the E.coli isolates(56.66%) were shown to carry mutations in gyrA and parC,igyra:Ser83Leu + Asp87Asn and parC:Ser80Iler.While.16.66 had only an alteration in gyrA:Ser83Leu.One isolate produced qnrB-like and two qnrS-like.Four isolates were CTXM-15 producers associated with TEM-1 producing in one case.Co-expression of bla_(LTV,M)_(15) and qnrB was determined in one E.coli isolate.Conclusions:Our findings suggested the community emergence of gyrA and parC alterations and Qnr determinants that contributed to the development and spread of fluoroquinolone resistance in Algerian E.coli isolates.
文摘<b>Background:</b> Typhoid fever is a major public health concern in developing countries. The upsurge in the occurrence of bacterial isolates that are resistant to nalidixic acid;with reduced susceptibility to ciprofloxacin in typhoidal <i>Salmonellae</i> constitutes a challenge to the clinician. <b>Methods:</b> In order to better understand the epidemiology of <i>Salmonella</i> infections in South India, <i>Salmonella typhi</i> isolates were screened from various healthcare centers. <i>Salmonella</i> isolates were identified by using standard phenotypic, serological, antibiotic susceptibility and molecular methods. <b>Results:</b> Among a total of 100 <i>S. typhi</i> isolates 9% were found to be multidrug resistant and 30% were nalidixic acid resistant. Isolates with reduced susceptibility to ciprofloxacin displays single base mutations in the gyrA gene. A very low rate of 1% resistance was found to ciprofloxacin. The only one isolate with ciprofloxacin MIC ≥ 4 μg/ml also showed single mutation in the QRDR of the gyrA gene in <i>S. typhi</i> (GenBank accession no. HQ176349-HQ176368). <b>Conclusions:</b> A very low rate of nalidixic acid resistance with reduced susceptibility to ciprofloxacin was observed in comparison to other endemic areas in isolates of <i>S. typhi</i> from Gulbarga, South India, with steadily increasing NAR <i>S. typhi</i> but decreasing MDR isolations over the study period. This is most likely due to an increased use of ciprofloxacin as a first line drug of choice over more traditional antimicrobial agents for the treatment of typhoid fever.
