Abstract
Introduction: Pseudomonads are very important as an opportunistic bacterium among gram-negative
bacteria. Class B beta-lactamases such as Verona imipenemase (VIM) and Imipenemase (IMP) are the most
important contributors to the resistance of gram-negative bacteria like Pseudomonas aeruginosa. These
enzymes were isolated from burn wounds in Zahedan due to extended spectrum beta-lactamase (ESBL)
activity and high resistance to β-lactamase antibodies (IMP and VIM) in P. aeruginosa isolates.
Objectives: This study was aimed to determine the frequency of VIM, IMP beta-lactamase genes in clinical
isolates of P. aeruginosa isolated from therapeutic centers of Zahedan.
Materials and Methods: In this descriptive cross-sectional study, 125 samples of P. aeruginosa from burn
wounds were collected from patients who were hospitalized in Zahedan as well as were cultured. Suspected
colonies of P. aeruginosa were identified using common biochemical methods. The Kirby Bayer method
was used to measure antibiotic susceptibility, and then the minimum inhibitory concentration (MIC) of
these strains was examined. The genotypes of the β-lactamase genes of IMP and VIM were investigated in
polymerase chain reaction (PCR) strains.
Results: In this study, 125 isolates of P. aeruginosa were found in 32 isolates (26%) producing ESBL. In
general, the resistance of P. aeruginosa to the antibiotics of imipenem, piperacillin, ceftazidime, cefotaxime,
ceftriaxone, levofloxacin, ciprofloxacin, gentamicin, amikacin, streptomycin, tetracycline, and carbenicillin
were 88%, 93%, 89%, 98%, 97%, 89%, 84%, 82%, 97%, 91%, 90% and 95%, respectively. According to
the PCR test, 32 isolates with ESBL enzymes were 43.75 and 18.75, respectively.
Conclusion: The prevalence of ESBLs and antibiotic resistance in the burn injuries of hospital is high
and requires such as antibiotic susceptibility test, rational administration of antibiotics and the control of
beneficial factors. The results showed that most of the samples were resistant to the drug and the frequency
of blaVIM genes was higher than blaIMP among the strains producing ESBLs.