فراوانی اینتگرون‌های کلاس I و II در ایزوله‌های بالینی سودوموناس آئروژینوزا مولد متالوبتالاکتاماز

Background and Objective: Pseudomonas aeruginosa is an opportunistic nosocomial pathogen. Evidence suggests that the incidence of enzyme-producing strains of Pseudomonas aeruginosa Metalo Beta Lactamases (MBL) is a major problem in the treatment of infections caused by this organism. The aim of this study was to investigate the frequency of class I and II integrons among metalobetalactamase producing Pseudomonas aeruginosa isolated from clinical samples from Zanjan hospitals. Materials and Methods: In this cross-sectional study, 120 Pseudomonas aeruginosa isolates from clinical specimens were collected from Zanjan hospitals in 2012-2013. After verifying isolates by biochemical tests, antibiotic susceptibility testing (Kirby-Baur method) was performed according to CLSI guidelines against 7 antibiotics. The DDST was then carried out for detection of MBLs. Finally, the presence of IntI1, IntI2, blaVIM and blaGIM genes was determined by PCR. Results: In our study, the highest and the lowest resistant patterns were related to Cefotaxime and Amikacin with 43.3% and 21.6%, respectively. Of 120 isolates, the metallo- beta-lactamase was detected in 35 (29%) isolates. According to results, the frequency of intI1, intI2, blaVIM genes in MBL producers were 32(91%), 3(9%), and 6(17%), respectively, but no blaGIM positive isolate was detected. Also all of IntI2 positive isolates carried IntI1 and blaVIM,, simultaneously. Conclusion: The results of this study indicate high frequency of class I integron gene among MBL producing Pseudomonas aeruginosa isolates. Due to the importance of integrons in dissemination of antibiotic resistance genes, detection and prevention of these elements are necessary. References 1- Kohlenberg A, Weitzel-Kage D, van der Linden P, et al. Outbreak of carbapenem-resistant Pseudomonas aeruginosa infection in a surgical intensive care unit. 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