Mirsalehian A, Akbari Nakhjavani F, Bahador A, Jabal Ameli F, Bigverdi R, Goli H,
Volume 68, Issue 10 (1-2011)
Abstract
Background: Pseudomonas aeruginosa is an important opportunistic pathogen causes clinical infections among
burn patients. Metallo-β-lactamases (MBLs) are important mechanisms of Carbapenem (drug of choice) resistance among Pseudomonas
aeruginosa isolates. The aims of this study were to determine the
antibiotic susceptibility pattern and to detect the prevalence of MBLs among Pseudomonas
aeruginosa
Methods: Initially, the antibiotic resistance patterns of 170 clinical
strains isolated from burn patients in Motahari
Hospital in Tehran, Iran
were determined by Kirby-Bauer disc diffusion method. All of the clinical isolates using two phenotypic and genotypic methods. Pseudomonas
aeruginosa isolates resistant to Imipenem were screened for production of MBL by E test with
Imipenem / Imipenem plus EDTA (E test MBL). PCR assay was performed for detection of blaVIM genes.
Results: Based on the study results, the percentage of
resistance was as below: Imipenem (10 μg) 52.9%, Amikacin (30 μg) 81.7%, Carbenicilin (100 μg) 74.7%, Polymixine B (300 unit) 10%, Ticarcilin (75 μg) 84.7%, Tobramycin (10 μg) 88.2%, Colisitin (10 μg) 34.1, Colisitin (25 μg) 28.3%. Of 90 Carbapenem resistant isolates, 10(11/1%)
isolates were positive by E test, all were sensitive to Colisitin and Polymixine B. All of the
Imipenem resistant Pseudomonas aeruginosa isolates were examined by PCR for the
presence of the blaVIM genes. All MBL-producing isolates carried blaVIM-1 genes.
Conclusion:
Considering the high prevalence and clinical importance of MBL-producing isolates,
rapid identification of them and use of the appropriate infection control
measures are necessary to prevent further spread of infections by these
organisms.
