Open AccessMolecular detection of metallo-β-lactamase geneblaVIM-1 in imipenem-resistantPseudomonas aeruginosastrains isolated from hospitalized patients in the hospitals of Isfahan
Author(s) -
Mansour Sedighi,
Hamid Vaez,
Mohsen Moghoofeie,
Shima Hadifar,
Golfam Oryan,
Jamshid Faghri
Publication year - 2015
Publication title -
advanced biomedical research
Language(s) - English
Resource type - Journals
ISSN - 2277-9175
DOI - 10.4103/2277-9175.151872
Subject(s) - imipenem , pseudomonas aeruginosa , microbiology and biotechnology , antimicrobial , drug resistance , agar dilution , minimum inhibitory concentration , agar diffusion test , polymerase chain reaction , antibiotics , medicine , antibiotic resistance , biology , virology , gene , bacteria , antibacterial activity , genetics
Background: Pseudomonas aeruginosa is an opportunistic human pathogen that causes serious problems, especially in people, who have immunodeficiency. In recent times, metallo-β-lactamase (MBLs) resistance in this bacterium has led to some difficulties in treating bacterial infections. The metallo-beta-lactamase family of genes, including blaVIM-1, is being reported with increasing frequency worldwide. The aim of this study is the detection of the metallo-β-lactamase gene blaVIM-1 in imipenem-resistant P. aeruginosa (IRPA) strains isolated from hospitalized patients. Materials and Methods: In this study, 106 P. aeruginosa samples were isolated from various nosocomial infections. The isolates were identified, tested for susceptibility to various antimicrobial agents by the Kirby-Bauer disk diffusion method, and all the imipenem-resistant isolates were screened for the presence of MBLs by using the combined disk (IMP-EDTA). The minimal inhibitory concentration (MIC) of imipenem was determined by E-test on the Mueller-Hinton agar. To detect the blaVIM-1 gene, the isolates were subjected to a polymerase chain reaction (PCR). Results: Of all the P. aeruginosa isolates, 62 (58.5%) were found to be imipenem-resistant P. aeruginosa (MIC ≥32 μg/ml). Twenty-six (42%) of the imipenem-resistant isolates were MBL positive. None of these isolates carried the blaVIM-1 gene using the PCR assay.Conclusion: The results demonstrated the serious therapeutic threat of the MBL-producing P. aeruginosa populations. The rate of imipenem resistance due to MBL was increased dramatically. Early detection and infection-control practices are the best antimicrobial strategies for this organism. None of MBL-producing isolates in this study carry the blaVIM-1 gene; therefore, another gene in the MBL family should be investigated