Objective: Class B carbapenemases are bacterial enzymes that catalyze the hydrolysis of β-lactam core antibiotics, except for monobactams. The objective of this study was to identify the carbapenemase gene bla<sub...Objective: Class B carbapenemases are bacterial enzymes that catalyze the hydrolysis of β-lactam core antibiotics, except for monobactams. The objective of this study was to identify the carbapenemase gene bla<sub>IMP</sub> in the genus Klebsiella at the Charles De Gaulle Pediatric University Hospital (CHUP-CDG) of Ouagadougou, Burkina Faso. Methods: The study involved 17 bacterial strains responsible for human infection and isolated from various biological samples during the period from 2009 to 2013. The strains were tested for antimicrobial susceptibility to cefotaxime, ceftazidime and imipenem using the Mueller-Hinton agar diffusion method. The carbapenemases resistance genes were detected by conventional PCR using specific primers at the molecular biology laboratory of CERBA/LABIOGENE, Ouagadougou, Burkina Faso. Results: The antibiotic susceptibility test showed high resistance of the 17 Klebsiella isolates tested to cephalosporins. A high cefotaxime-resistance rate (82.35%) and ceftazidime-resistance rate (88.23%) was found among the strains tested against 11.76% resistance rate for imipenem. Analysis of PCR products by gel electrophoresis revealed 4 strains (23.53%) with bla<sub>IMP</sub>-type gene. Conclusion: Klebsiella is a well-known bacterium in clinical practice. The present study demonstrated the bla<sub>IMP</sub>-type gene in cephalosporin-resistant strains of Klebsiella at CHUP-CDG. More effective monitoring and treatment solutions are needed to prevent the spread of these resistant strains.展开更多
Introduction:Carbapenem-resistant Klebsiella pneumoniae(CRKP)poses a significant global public health threat.The dissemination of resistance is accelerated by plasmids harboring multiple carbapenemase genes,posing a p...Introduction:Carbapenem-resistant Klebsiella pneumoniae(CRKP)poses a significant global public health threat.The dissemination of resistance is accelerated by plasmids harboring multiple carbapenemase genes,posing a particular challenge to the limited treatment options,including ceftazidimeavibactam.Methods:In this study,a CRKP strain,KpBSI024,was isolated from a patient with bloodstream infection in the intensive care unit of a tertiary hospital in China.The whole-genome sequencing combined with bioinformatic analysis was used to investigate the structural features of plasmids and associated resistance genes.In addition,conjugation experiments were conducted to assess the transferability of the resistance plasmid.Results:KpBSI024 exhibited resistance to carbapenems and ceftazidime-avibactam and was identified as sequence type ST1514.Whole-genome sequencing revealed that two carbapenemase genes,bla_(KPC-2) and bla_(IMP-4),coexisted on a 53 kb IncP6-type plasmid.This plasmid exhibited a complex structure,likely formed through multiple recombination events mediated by IS26 between plasmids of different Inc types.Although the resistance plasmid encodes a type IV secretion system,it lacks a relaxase gene and is therefore non-self-transmissible;however,it could be transferred at low frequency to Escherichia coli with the assistance of a conjugative plasmid.The growth of the transconjugants was not affected by the acquisition of the resistance plasmid,and they displayed resistance profiles to carbapenems and ceftazidime-avibactam similar to the donor strain.Conclusions:The coexistence of bla_(KPC-2) and bla_(IMP-4) on an IncP-type plasmid in a clinical K.pneumoniae isolate highlights the critical role of recombination events in the dissemination of resistance genes.The emergence of such multidrug-resistant plasmids underscores the urgent need for genomic surveillance and the development of innovative antimicrobial strategies to control the spread of highrisk resistance plasmids.展开更多
文摘Objective: Class B carbapenemases are bacterial enzymes that catalyze the hydrolysis of β-lactam core antibiotics, except for monobactams. The objective of this study was to identify the carbapenemase gene bla<sub>IMP</sub> in the genus Klebsiella at the Charles De Gaulle Pediatric University Hospital (CHUP-CDG) of Ouagadougou, Burkina Faso. Methods: The study involved 17 bacterial strains responsible for human infection and isolated from various biological samples during the period from 2009 to 2013. The strains were tested for antimicrobial susceptibility to cefotaxime, ceftazidime and imipenem using the Mueller-Hinton agar diffusion method. The carbapenemases resistance genes were detected by conventional PCR using specific primers at the molecular biology laboratory of CERBA/LABIOGENE, Ouagadougou, Burkina Faso. Results: The antibiotic susceptibility test showed high resistance of the 17 Klebsiella isolates tested to cephalosporins. A high cefotaxime-resistance rate (82.35%) and ceftazidime-resistance rate (88.23%) was found among the strains tested against 11.76% resistance rate for imipenem. Analysis of PCR products by gel electrophoresis revealed 4 strains (23.53%) with bla<sub>IMP</sub>-type gene. Conclusion: Klebsiella is a well-known bacterium in clinical practice. The present study demonstrated the bla<sub>IMP</sub>-type gene in cephalosporin-resistant strains of Klebsiella at CHUP-CDG. More effective monitoring and treatment solutions are needed to prevent the spread of these resistant strains.
基金Supported by the National Key Research and Development Program of China(2024YFE0199000)the National Natural Science Foundation of China(82000011)+1 种基金Hainan Provincial Natural Science Foundation of China(825RC764)the Decision-Making Consultation Project of Shanghai Jiao Tong University(JCZXSJB2023-13).
文摘Introduction:Carbapenem-resistant Klebsiella pneumoniae(CRKP)poses a significant global public health threat.The dissemination of resistance is accelerated by plasmids harboring multiple carbapenemase genes,posing a particular challenge to the limited treatment options,including ceftazidimeavibactam.Methods:In this study,a CRKP strain,KpBSI024,was isolated from a patient with bloodstream infection in the intensive care unit of a tertiary hospital in China.The whole-genome sequencing combined with bioinformatic analysis was used to investigate the structural features of plasmids and associated resistance genes.In addition,conjugation experiments were conducted to assess the transferability of the resistance plasmid.Results:KpBSI024 exhibited resistance to carbapenems and ceftazidime-avibactam and was identified as sequence type ST1514.Whole-genome sequencing revealed that two carbapenemase genes,bla_(KPC-2) and bla_(IMP-4),coexisted on a 53 kb IncP6-type plasmid.This plasmid exhibited a complex structure,likely formed through multiple recombination events mediated by IS26 between plasmids of different Inc types.Although the resistance plasmid encodes a type IV secretion system,it lacks a relaxase gene and is therefore non-self-transmissible;however,it could be transferred at low frequency to Escherichia coli with the assistance of a conjugative plasmid.The growth of the transconjugants was not affected by the acquisition of the resistance plasmid,and they displayed resistance profiles to carbapenems and ceftazidime-avibactam similar to the donor strain.Conclusions:The coexistence of bla_(KPC-2) and bla_(IMP-4) on an IncP-type plasmid in a clinical K.pneumoniae isolate highlights the critical role of recombination events in the dissemination of resistance genes.The emergence of such multidrug-resistant plasmids underscores the urgent need for genomic surveillance and the development of innovative antimicrobial strategies to control the spread of highrisk resistance plasmids.
