Objective:To assess and characterize antibiotic resistance in Acinetobacter baumannii strains recovered from 5 health-care facilities in Algiers.Methods:Antibiotic susceptibility testing was performed by agar diffusio...Objective:To assess and characterize antibiotic resistance in Acinetobacter baumannii strains recovered from 5 health-care facilities in Algiers.Methods:Antibiotic susceptibility testing was performed by agar diffusion and agar dilution methods,resistance genes were identified by PCR and sequencing,and molecular typing of isolates was carried out by enterobacterial repetitive intergenic consensus-PCR(ERIC-PCR).Results:Among 125 tested isolates,117(93.6% ) were multidrug-resistant.of which 94(75.2% ) were imipenem resistant.The bla_(ADC)and bla_(OXA-51-like) genes were detected in all isolates,in association with ISAba I sequence in 84% and 8% (imipenem resistant) of isolates,respectively.The bla_(OXA-23-like) and bla_(OXA-24-like)carbapenemase genes were delected in 67.02% and 20.21% of imipenem-resistant isolates,respectively.The bla_(OXA-23-like) gene is linked to ISAba1 or ISAba4 elements.The metallo-β-lactamase NDM-1 gene was found in 10(10.6% ) imipenem-resisianl strains from three hospitals,it is linked to ISAba125 clement in nine strains.Extended spectrum β-lactamases production was not detected.Imipenem and cefotaxime resistance phenolypes could not be transferred to Escherichia coli by conjugation.Outer membrane protein CarO gene was not delected in four imipenem-resisianl isolates.The aac(6')-1b.sul1,sul2,tetA and tetB genes were present in 5.31% .36.17% .77.65% .1.06% and 65.92% of strains,respectively.Class 1 integrons were detected in 23.4% strains.KRIC-PCR typing showed a genetic diversity among bla_(OXA-23-like) and bla_(OXA-24-like) positive strains,while clonality was observed among bla_(NDM-1)positives.Conclusions:This study highlighted the high prevalence of imipenem resistance in Acinetobacter baumannii in Algiers hospitals mediated mainly by bla_(OXA-23-like),bla_(OXA-24-like),and bla_(NDM-1) genes.展开更多
基金supported by grants from National Fund for the Research and National Agency for the Development of Research in Health(Algeria)
文摘Objective:To assess and characterize antibiotic resistance in Acinetobacter baumannii strains recovered from 5 health-care facilities in Algiers.Methods:Antibiotic susceptibility testing was performed by agar diffusion and agar dilution methods,resistance genes were identified by PCR and sequencing,and molecular typing of isolates was carried out by enterobacterial repetitive intergenic consensus-PCR(ERIC-PCR).Results:Among 125 tested isolates,117(93.6% ) were multidrug-resistant.of which 94(75.2% ) were imipenem resistant.The bla_(ADC)and bla_(OXA-51-like) genes were detected in all isolates,in association with ISAba I sequence in 84% and 8% (imipenem resistant) of isolates,respectively.The bla_(OXA-23-like) and bla_(OXA-24-like)carbapenemase genes were delected in 67.02% and 20.21% of imipenem-resistant isolates,respectively.The bla_(OXA-23-like) gene is linked to ISAba1 or ISAba4 elements.The metallo-β-lactamase NDM-1 gene was found in 10(10.6% ) imipenem-resisianl strains from three hospitals,it is linked to ISAba125 clement in nine strains.Extended spectrum β-lactamases production was not detected.Imipenem and cefotaxime resistance phenolypes could not be transferred to Escherichia coli by conjugation.Outer membrane protein CarO gene was not delected in four imipenem-resisianl isolates.The aac(6')-1b.sul1,sul2,tetA and tetB genes were present in 5.31% .36.17% .77.65% .1.06% and 65.92% of strains,respectively.Class 1 integrons were detected in 23.4% strains.KRIC-PCR typing showed a genetic diversity among bla_(OXA-23-like) and bla_(OXA-24-like) positive strains,while clonality was observed among bla_(NDM-1)positives.Conclusions:This study highlighted the high prevalence of imipenem resistance in Acinetobacter baumannii in Algiers hospitals mediated mainly by bla_(OXA-23-like),bla_(OXA-24-like),and bla_(NDM-1) genes.
