en ميکروبيولوژي Microbiology پژوهشي Research <p><b>Background:</b> Pseudomonas aeruginosa is the causing agent of many hospital infections and metallo-beta-lactamases (MBL) are being reported with increasing frequency. The aim of this study was to determine the frequency of metallo-&beta-lactamases (MBL) and VIM-1 gene in multidrug-resistant strains of <i>P. aeruginosa</i> isolates and to compare the methods of phenotypic and molecular detection.<br> <b>Materials and Methods:</b> In 2011- 2012, 50 samples of non &ndash; duplicate <i>P. aeruginosa</i> were isolated from intensive care units and tested for MBL production using phenotypic methods. Minimal Inhibitory concentrations (MICs) were determined by commercial micro dilution panels. The presence of metallo-&beta-lactamase (MBL) genes was established by polymerase chain reaction (PCR) with specific primers targeting the bla (VIM) genes.<br> <b>Results:</b> We used 50 clinical isolates amongst which 18 (%36) were found resistant to imipenem. Productions of MBL were detected in 15 (30%) isolates applying phenotypic method. PCR assay showed that 9 (18%) isolates carried aVIM-1 gene. MBL- producing strains were shown 100% resistant to cefepime, ceftazidime, ceftriaxone, cefotaxime and imipenem. Amikacin and ofloxacin appeared to be the most active antimicrobial agent.<br> <b>Conclusion:</b> These findings demonstrate the emergence of bla (VIM-1) producing<i> P. aeruginosa</i> in North of Iran. VIM metallo-beta-lactamases producing<i> P. aeruginosa</i> strains can cause serious infections that are difficult to treat, therefore, there is a need for rapid identification and the timely implementation of infection control measures in combination with systematic surveillance to monitor its potential clonal spread.</p> Pseudomonas aeruginosa, metallo-beta-lactamases, Imipenem-resistant, bla (VIM-1) gene 28 33 http://rmm.mazums.ac.ir/browse.php?a_code=A-10-701-1&slc_lang=en&sid=1 Ramazan Rajabiana Ramazan69@yahoo.com 1 10031947532846005890 No Infectious Diseases and Tropical Medicine Research Center, Babol University of Medical Sciences, Babol, Iran Fariba Asgharpour F_asgharpour@yahoo.com 2 10031947532846005891 No Faculty of Para-Medicine; Babol University of Medical Sciences, Babol, Iran Zahra Moulana 3 10031947532846005892 Yes Infectious Diseases and Tropical Medicine Research Center, Babol University of Medical Sciences, Babol, Iranciences, Babol, Iran