Beta-lactamases profile among multidrug-resistant Pseudomonas aeruginosa isolate from different clinical samples

In this study, a total of 112 microbiological swab samples were obtained from different clinics of hospitals in the city of Babylon, between December 2021 and February 2022. Positive bacterial growth was observed in 100 (89.2%) of these samples, while bacterial growth was not observed in 12 (10.8%) samples. According to clinics, Pseudomonas aeruginosa was identified in a total of 50 isolates, 12 (24%) on wound swab, 28 (56% on burn swab), ear swab 3 (6%), and 7 (14%) isolates from the feet of diabetic patients. All isolates were investigated with cetrimid agar selective medium for P. aeruginosa and validated by PCR to detect the P. aeruginosa 16S rRNA amplicon. According to the antibiogram test results, in 50 P. aeruginosa isolates, the results of the Resistance phenotypes showed that 50% of the isolates were MDR. Phenotypic investigation of β-lactamase was performed using the Combination Disc Test (β-lactam/β-lactam+β-lactamase inhibitor) using three systems (Piperacilin/Piperacillin-Tazobactam; Ceftazidime / Ceftazidime - Tazobactam and Ticarcillin / Ticarcillin-Clavulanate). The presence of β-lactamase in 50 P.aeruginosa isolates obtained was 78%, 40% and 72%, respectively, compared to three different antibiotic disc combinations. PCR was used to investigate the presence of three different β-lactamase genes. According to the PCR results, blaTEM was detected in 98%, blaCTX-M-1 50% and blaSHIV 38% in 50 P.aeruginosa isolates. When the phenotypic and genotypic detection of 50 isolates producing P. aeruginosa β-Lactypic were compared, 43 isolates were Phenotypic positive/Genotypic positive (86%), Phenotypic positive/Genotypic negative 1 isolate (2%), and Phenotypic negative/Genotypic positive 6 isolates (12%). detected. When the distribution of resistance genes between both MDR and non-MDR P. aeruginosa burn isolates was examined; It can be concluded that phenotypic analysis may not reflect the presence of resistance genes, however, it can be concluded that blaTEM and blaCTX-M-1 may be responsible for the existing resistance against different antibiotic classes.