Evaluation of KPC-2 and OXA-10 Type of Extended- Spectrum β- Lactamase (ESBL) Genes in Clinical Isolates of the Pseudomonas aeruginosa and Acinetobacter Baumanii

Existence of extended spectrum B-lactamase (ESBL) genes plays an important role in spreading of β-lactam antibiotic resistance in the strains producing of these enzymes. The resistance of gram-negative bacteria, to different antimicrobial agents, especially β-lactam and carbapenem, has increasingly been reported. This study was conducted to determine antibiotic resistance and the prevalence of KPC-2 and OXA-10 β-lactamases in P. aeruginosa and A. baumannii isolates by Duplex PCR. In this study, non-fermentative bacilli collected from Alinasab and Shohada hospitals in Tabriz and Imam Khomeini hospital in Uremia, were subjected to bacteriological tests. The samples were cultured and identified according to standard methods the antibiotic resistance and antagonistic effects of drugs consumed and Determine of multidrug-resistant strains (MDR) were assayed by Disc diffusion Agar method. MIC determination imipenem and piperacillin antibiotics was conducted by E-test method. Phenotypic detection of extended-spectrum β-lactamase enzyme (ESBLs) by using disk diffusion Agar Method (ceftazidime, ceftriaxone, Aztronam) and Combined Disk Method. DNA of studied bacteria was extracted by DNA extraction Kit and examined for the existence of KPC-2 and OXA-10 gene by Duplex PCR method using 16srRNA specific primers. Most of Pseudomonas aeruginosa isolates were resistant to carbenicillin (72.7%) and Acinetobacter baumannii isolates of the carbenicillin, ceftazidime, ceftriaxone and aztreonam (92.9%). Antagonistic effects of imipenem with ceftazidime, ceftriaxone, Aztronam and Pipracillin were observed in 25.7%, 22.7%, 19.6% and 6.6% in pseudomonas aeruginosa isolates, respectively. Meanwhile, this effect was not observed in Acinetobacter baumannii isolates. Fifty-three isolates (66.25%) From studied ones were identified as MDR. Most of the resistance by E-test in both strains, Pseudomonas aeruginosa 38 (100%) and Acinetobacter baumannii 10 (90.9%) was observed compared to piperacillin. In this study, from 80 non-fermentative isolates, 29 (36.2%) were ESBL positive phenotypically. In spite of that from all isolates, 53(66.2%) and 57(71.2%) were shown KPC-2 and OXA-10 genes respectively. Depending of bacteria the KPC-2 gene in P. aeruginosa and A. baumannii (69.7%, 50%) and OXA-10 type were (72.7%, 64.3%), respectively. Due to extensive acquisition of drug resistance genes in clinical isolates, According to the results of Antibiotic for treatment in hospitals not enough and the need for continuous monitoring of strains generating broad-spectrum beta-lactamase enzymes and extensive carbamazepines and periodic changes in the treatment protocol for infections.