The increased prevalence of β-lactamase is one of the main factors in resistance to β-lactams in Pseudomonas aeruginosa. This study aimed to investigate the prevalence of blaVEB, blaPER, and blaGES genes in β-lactam-resistant P. aeruginosa. We collected 100 non-duplicated clinical isolates of P. aeruginosa and identified them by standard tests. Using disk agar diffusion test, we detected the β-lactam-resistant isolates and extracted the DNAs of the isolates by alkaline lysis method. Then, the prevalence of blaVEB, blaPER and blaGES genes were detected by PCR method. The results were assessed by SPSS 21 software and Chi-square test. Out of 100 isolates, 43% were detected as resistant against at least one of the beta-lactams tested. Piperacillin-tazobactam was the most effective antibiotic, while 39% and 37% of the isolates were resistant to aztreonam and meropenem, respectively. A significant relationship was observed between the resistance to tested antibiotics and the presence of blaVEB, blaGES, and blaPER genes. Among 43 isolates that were resistant to at least one of the tested β-lactams, 93.02%, 83.72%, and 81.39% of them carried blaVEB, blaGES, and blaPER genes, respectively. According to this study and due to high prevalence of β-lactam resistance genes, it is better to check the level of antibiotic resistance and resistance genes for better management of patients with infection caused by this bacterium. Also, high prevalence of class A β-lactamases indicates the significant role of these enzymes in emerging resistance to beta-lactams.
Citation: Saboura Haghighi, Hamid Reza Goli. High prevalence of blaVEB, blaGES and blaPER genes in beta-lactam resistant clinical isolates of Pseudomonas aeruginosa[J]. AIMS Microbiology, 2022, 8(2): 153-166. doi: 10.3934/microbiol.2022013
The increased prevalence of β-lactamase is one of the main factors in resistance to β-lactams in Pseudomonas aeruginosa. This study aimed to investigate the prevalence of blaVEB, blaPER, and blaGES genes in β-lactam-resistant P. aeruginosa. We collected 100 non-duplicated clinical isolates of P. aeruginosa and identified them by standard tests. Using disk agar diffusion test, we detected the β-lactam-resistant isolates and extracted the DNAs of the isolates by alkaline lysis method. Then, the prevalence of blaVEB, blaPER and blaGES genes were detected by PCR method. The results were assessed by SPSS 21 software and Chi-square test. Out of 100 isolates, 43% were detected as resistant against at least one of the beta-lactams tested. Piperacillin-tazobactam was the most effective antibiotic, while 39% and 37% of the isolates were resistant to aztreonam and meropenem, respectively. A significant relationship was observed between the resistance to tested antibiotics and the presence of blaVEB, blaGES, and blaPER genes. Among 43 isolates that were resistant to at least one of the tested β-lactams, 93.02%, 83.72%, and 81.39% of them carried blaVEB, blaGES, and blaPER genes, respectively. According to this study and due to high prevalence of β-lactam resistance genes, it is better to check the level of antibiotic resistance and resistance genes for better management of patients with infection caused by this bacterium. Also, high prevalence of class A β-lactamases indicates the significant role of these enzymes in emerging resistance to beta-lactams.
Multi-drug Resistant
D-Alanine-D-Alanine
Beta-lactams
Extended-spectrum Beta-lactamase
Minimum Inhibitory Concentration
Trypticase Soy Broth
Clinical and Laboratory Standards Institute
American Type Culture Collection
Sodium Dodecyl Sulfate
Optical Density
Polymerase Chain Reaction
Intensive Care Unit
Cardiac Care Unit
Extensively Drug Resistant
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