Trauma Research Center, Kashan University of Medical Sciences, Kashan, IR Iran
Department of Microbiology and Immunology, School of Medicine, Kashan University of Medical Sciences, Kashan, IR Iran
Department of Parasitology and Mycology, School of Medicine, Alborz University of Medical Sciences, Karaj, IR Iran
Metallo-β-lactamase-production among Gram-negative bacteria, including Pseudomonas aeruginosa, has become a challenge for treatment of infections due to these resistant bacteria.
The aim of the current study was to evaluate the metallo-β-lactamase-production and carriage of bla-VIM genes among carbapenem-resistant P. aeruginosa isolated from burn wound infections.
Patients and Methods
A cross-sectional study was conducted from September 2014 to July 2015. One hundred and fifty P. aeruginosa isolates were recovered from 600 patients with burn wound infections treated at Imam-Musa-Kazem Hospital in Isfahan city, Iran. Carbapenem-resistant P. aeruginosa isolates were screened by disk diffusion using CLSI guidelines. Metallo-β-lactamase-producing P. aeruginosa isolates were identified using an imipenem-EDTA double disk synergy test (EDTA-IMP DDST). For detection of MBL genes including bla-VIM-1 and bla-VIM-2, polymerase chain reaction (PCR) methods and sequencing were used.
Among the 150 P. aeruginosa isolates, 144 (96%) were resistant to imipenem by the disk diffusion method, all of which were identified as metallo-β-lactamase-producing P. aeruginosa isolates by EDTA-IMP DDST. Twenty-seven (18%) and 8 (5.5%) MBL-producing P. aeruginosa isolates harbored bla-VIM-1 and bla-VIM-2 genes, respectively.
Our findings showed a high occurrence of metallo-β-lactamase production among P. aeruginosa isolates in burn patient infections in our region. Also, there are P. aeruginosa isolates carrying the bla-VIM-1 and bla-VIM-2 genes in Isfahan province.