Medical Laboratory Journal

fa Prevalence of Extended-Spectrum β-Lactamases Genes in Clinical Isolates of Pseudomonas aeruginosa تحقيقي Original Paper <div>ABSTRACT             Background and Objectives: Pseudomonas aeruginosa is an opportunistic pathogen resistant to various antibiotics. The aim of the present study was to study resistant patterns in clinical isolates of P. aeruginosa, classify them into pandrug resistance (PDR), extensive drug resistance (XDR) and multidrug resistance (MDR) groups, and identify extended-spectrum β-lactamase (ESBL)-positive isolates using the phenotypic and genotypic methods.             Methods: This cross-sectional study was conducted on 161 P. aeruginosa isolates collected from the city of Isfahan, Iran. Antibiotic susceptibility tests were performed using 11 antimicrobial agents. ESBL-positive strains were identified using the phenotypic and genotypic methods.             Results: The highest level of antibiotic resistance was observed against ceftazidime (77.64%). None of the isolates was resistant to polymyxin B. In the phenotypic method, 64 isolates (39.75%) were found as ESLB-positive, whereas 132 isolates (81.98%) were ESBL-positive in the genotypic method. The number of ESBL-positive isolates in the genotypic method was significantly higher than in the phenotypic method. The frequency of XDR and MDR isolates was 50.93% and 27.32%, respectively. None of the isolates was PDR. The frequency of the blaTEM gene was significantly higher than other genes (P<0.0001).             Conclusion: It was revealed that the genotypic method was much more accurate in identifying ESBL-positive strains than the phenotypic method. Therefore, use of the molecular method may increase the chance of successful treatment with antibiotics of the β-lactam family.             Keywords: Drug Resistance, <a href="https://www.ncbi.nlm.nih.gov/mesh/68001618"> β-lactamases</a>, Pseudomonas aeruginosa.</div> Drug Resistance, β-lactamases, Pseudomonas aeruginosa. 34 41 http://mlj.goums.ac.ir/browse.php?a_code=A-10-1-540&slc_lang=fa&sid=1 Majid Komijani M-Komijani@araku.ac.ir 100319475328460014586 100319475328460014586 Yes Department of Biology, Faculty of Science, Arak University, Arak 38156-8-8349, Iran Khashayar Shahin 100319475328460014587 100319475328460014587 No Department of Biology, Faculty of Sciences, University of Isfahan, Isfahan, Iran and State Key Laboratory Cultivation Base of MOST, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, PR China Mohadeseh Barazandeh 100319475328460014588 100319475328460014588 No State Key Laboratory Cultivation Base of MOST, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, PR China Mehdi Sajadi 100319475328460014589 100319475328460014589 No Department of Microbiology, Amin Hospital, Isfahan University of Medical Sciences, Isfahan, Iran