Frequency of Metalo beta Lactamase genes, bla IMP1, INT 1 in Acinetobacter baumanii isolated from burn patients North of Iran

Abstract

Objective: Acinetobacter baumanii is one of the most important pathogenic bacteria causing infectious diseases. The aim of this study was to evaluate the antibiotic resistance and determine the frequency of β-lactamase and class I integron genes in clinical strains of Acinetobacter baumanii isolated from burn patients in Sari, North of Iran. Method: A. baumanii specimens were collected from 2016 to 2019. After culture in a standard medium, the presence of A. baumanii was confirmed by biochemical tests. Antibacterial sensitivity test against ciprofloxacin, imipenem, meropenem, Cefepime, ceftazidime, gentamicin, amikacin and colistin was performed using disc diffusion method on the Muller-Hinton agar medium. Finally, polymerase chain reaction was performed to determine the resistance genes. Results: A total of 150 A. baumanii were isolated. The results of the pattern of resistance of A. baumanii to the antibiotics tested were as follows: ceftazidime (100), cefepime (94), meropenem (91), imipenem (88), ciprofloxacin (80), amikacin (78), gentamicin (63), colistin (10). The study showed that 31 of the isolates produced the metallo-β-lactamases (MBLs) enzyme. Finally, by PCR method, blaIMP, blaVIM and class I integron were identified in, 45, 35 and 60 of these isolates, respectively. Conclusion: This study revealed an increased frequency of MBL-encoding genes (VIM, IMP) and class I integron in A. baumannii isolates. Also, the results of this study showed that the rate of resistant to antibiotic among A. baumanii is high. In the present study, the only antibiotic that was suitable for the treatment of these patients was colistin. These results suggest further studies on the logical use of the drug in the treatment of A. baumanii. © 2020 Elsevier Inc