Background and Purpose: The reintroduction of colistin as a last resort treatment against multi-resistant Gram-negative bacilli, is currently challenged by the emergence of colistin-resistant bacteria. The aim of this...Background and Purpose: The reintroduction of colistin as a last resort treatment against multi-resistant Gram-negative bacilli, is currently challenged by the emergence of colistin-resistant bacteria. The aim of this study was to assess the susceptibility of Pseudomonas and Acinetobacter strains to colistin, to identify carbapenemase production, and to investigate the plasmid genes involved in colistin resistance and carbapenemase production. Methodology: In order to establish the susceptibility profiles of 17 strains of Pseudomonas and Acinetobacter to colistin, their Minimum Inhibitory Concentrations (MICs) were determined using the liquid microdilution method. The possible production of carbapenemases was investigated with the modified Carbapenem Inactivation Method (mCIM). The search for genes encoding carbapenemases (bla<sub>OXA</sub>, bla<sub>IMP</sub>, bla<sub>Carba</sub>) and those responsible for plasmid resistance to colistin (mcr-1 and mcr-2) was performed by conventional PCR. Results and Conclusion: Ninety-four percent (94%) (16/17) of the strains were resistant to colistin. Intraspecies distribution was 50% (8/16), 31% (5/16), 13% (2/16) and 6% (1/16) for Acinetobacter baumannii, Pseudomonas aeruginosa, Pseudomonas luteola, and Pseudomonas fluorescens, respectively. Twenty-nine percent (29%) (6/17) of the strains produced carbapenemases. No mcr-1 and mcr-2 plasmid genes were detected. On the other hand, 17.6% (3/17) of the strains possessed the carbapenemase genes distributed as follows: Carba type (60%), OXA type (40%) and IMP type (0%). The results of this study highlight a high resistance to colistin in strains belonging to the genera Acinetobacter and Pseudomonas, and some of these strains produce carbapenemases.展开更多
<b><span style="font-family:Verdana;">Background and Purpose: </span></b><span style="font-family:;" "=""><span style="font-family:Verdana;"...<b><span style="font-family:Verdana;">Background and Purpose: </span></b><span style="font-family:;" "=""><span style="font-family:Verdana;">Diarrhoeagenic </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> (DEC) is one of the germs responsible for childhood diarrhea in developing countries. This study aims at determining the prevalence of the five main pathotypes of DEC isolated from faeces of children under five years old with diarrhea or not, living in the city of Koula-Moutou. </span><b><span style="font-family:Verdana;">Methodology: </span></b><span style="font-family:Verdana;">Isolates of </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> were phenotypically screened on chromID</span><sup><span style="font-family:Verdana;">TM</span></sup><span style="font-family:Verdana;"> agar and molecularly by multiplex PCR to detect the </span><span><span style="font-family:Verdana;">presence of enteroaggregative </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> (EAEC), enteropathogenic </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> (EPEC), </span></span><span style="font-family:Verdana;">enterotoxigenic </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> (ETEC), enterohemorragic </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> (EHEC) and enteroinvasive </span><i><span style="font-family:Verdana;">E. coli </span></i><span style="font-family:Verdana;">(EIEC). The evaluation of their sensitivity to 12 </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-lactam antibiotic molecules was carried out by Kirby Bauer method. This method has also made it possible to characterize phenotypically the different </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-lactamases produced. </span><b><span style="font-family:Verdana;">Results and Conclusion: </span></b><span style="font-family:Verdana;">Overall, at least one DEC pathovar was detected in the 63 </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> strains with phenotypic and molecular frequencies </span><span style="font-family:Verdana;">of 63.5% and 68.5% respectively. Thus, ETEC (28.3%) and EHEC (28.3%)</span><span style="font-family:Verdana;"> were the most frequent DEC in diarrheal isolates. ETEC/EHEC hybrid was recorded in both groups with rates of 7.5% in diarrheal cases and 10.0% for </span><span><span style="font-family:Verdana;">controls. The results showed produced carbapenemase type </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-lactamases</span></span><span style="font-family:Verdana;"> (31.7%), followed by ESBL (24.4%) and few produced high level penicillinases (4.9%). The DEC, in particular ETEC and EHEC are most likely the epidemiological agents responsible for childhood diarrhea in this study.</span></span>展开更多
文摘Background and Purpose: The reintroduction of colistin as a last resort treatment against multi-resistant Gram-negative bacilli, is currently challenged by the emergence of colistin-resistant bacteria. The aim of this study was to assess the susceptibility of Pseudomonas and Acinetobacter strains to colistin, to identify carbapenemase production, and to investigate the plasmid genes involved in colistin resistance and carbapenemase production. Methodology: In order to establish the susceptibility profiles of 17 strains of Pseudomonas and Acinetobacter to colistin, their Minimum Inhibitory Concentrations (MICs) were determined using the liquid microdilution method. The possible production of carbapenemases was investigated with the modified Carbapenem Inactivation Method (mCIM). The search for genes encoding carbapenemases (bla<sub>OXA</sub>, bla<sub>IMP</sub>, bla<sub>Carba</sub>) and those responsible for plasmid resistance to colistin (mcr-1 and mcr-2) was performed by conventional PCR. Results and Conclusion: Ninety-four percent (94%) (16/17) of the strains were resistant to colistin. Intraspecies distribution was 50% (8/16), 31% (5/16), 13% (2/16) and 6% (1/16) for Acinetobacter baumannii, Pseudomonas aeruginosa, Pseudomonas luteola, and Pseudomonas fluorescens, respectively. Twenty-nine percent (29%) (6/17) of the strains produced carbapenemases. No mcr-1 and mcr-2 plasmid genes were detected. On the other hand, 17.6% (3/17) of the strains possessed the carbapenemase genes distributed as follows: Carba type (60%), OXA type (40%) and IMP type (0%). The results of this study highlight a high resistance to colistin in strains belonging to the genera Acinetobacter and Pseudomonas, and some of these strains produce carbapenemases.
文摘<b><span style="font-family:Verdana;">Background and Purpose: </span></b><span style="font-family:;" "=""><span style="font-family:Verdana;">Diarrhoeagenic </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> (DEC) is one of the germs responsible for childhood diarrhea in developing countries. This study aims at determining the prevalence of the five main pathotypes of DEC isolated from faeces of children under five years old with diarrhea or not, living in the city of Koula-Moutou. </span><b><span style="font-family:Verdana;">Methodology: </span></b><span style="font-family:Verdana;">Isolates of </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> were phenotypically screened on chromID</span><sup><span style="font-family:Verdana;">TM</span></sup><span style="font-family:Verdana;"> agar and molecularly by multiplex PCR to detect the </span><span><span style="font-family:Verdana;">presence of enteroaggregative </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> (EAEC), enteropathogenic </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> (EPEC), </span></span><span style="font-family:Verdana;">enterotoxigenic </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> (ETEC), enterohemorragic </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> (EHEC) and enteroinvasive </span><i><span style="font-family:Verdana;">E. coli </span></i><span style="font-family:Verdana;">(EIEC). The evaluation of their sensitivity to 12 </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-lactam antibiotic molecules was carried out by Kirby Bauer method. This method has also made it possible to characterize phenotypically the different </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-lactamases produced. </span><b><span style="font-family:Verdana;">Results and Conclusion: </span></b><span style="font-family:Verdana;">Overall, at least one DEC pathovar was detected in the 63 </span><i><span style="font-family:Verdana;">E. coli</span></i><span style="font-family:Verdana;"> strains with phenotypic and molecular frequencies </span><span style="font-family:Verdana;">of 63.5% and 68.5% respectively. Thus, ETEC (28.3%) and EHEC (28.3%)</span><span style="font-family:Verdana;"> were the most frequent DEC in diarrheal isolates. ETEC/EHEC hybrid was recorded in both groups with rates of 7.5% in diarrheal cases and 10.0% for </span><span><span style="font-family:Verdana;">controls. The results showed produced carbapenemase type </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-lactamases</span></span><span style="font-family:Verdana;"> (31.7%), followed by ESBL (24.4%) and few produced high level penicillinases (4.9%). The DEC, in particular ETEC and EHEC are most likely the epidemiological agents responsible for childhood diarrhea in this study.</span></span>
