Prevalence and Molecular Characterization of Plasmid-mediated Extended-Spectrum β-Lactamase Genes (balaTEM, blaCTX and blASHV) Among Urinary Escherichia coli Clinical Isolates in Mashhad, Iran

• Published in: Iranian journal of basic medical sciences Vol. 15; no. 3; pp. 833 - 839
• Main Authors: Nakhaei Moghaddam, Mahboobeh, Forghanifard, Mohammad Mahdi, Moshrefi, Sheila
• Format: Journal Article
• Language: English
• Published: Iran Mashhad University of Medical Sciences 01.05.2012
• Subjects: Original; Urinary tract infection; Extended-spectrum beta-lactamase; Escherichia coli; Antibiotic resistance
• ISSN: 2008-3866; 2008-3874

Extended-spectrum beta-lactamase (ESBL) producing bacteria have an important role in nosocomial infections. Due to the limited availability of information about the molecular epidemiology of ESBL producing bacteria in Mashhad, we decided to investigate about TEM, CTX and SHV ESBLs among urinary Escherichia coli isolates in Mashhad, a city in northeast Iran. One hundred and eleven clinical isolates of E. coli were diagnosed from hospitalized patients in 2009. After performing antibiogram and phenotypic confirmation test, polymerase chain reaction (PCR) was performed by blaTEM, blaSHV and blaCTX primers and restriction digestion was carried out using PstI and TaqI (Fermentas-Lithuania) for confirmation. ESBL producers of E. coli isolates were 33.3%. Among 37 ESBL-producing isolates, 35 (94.6%), 21 (56.8%) and 5 (13.5%) were shown to have blaCTX, blaTEM and blaSHV, genes respectively. Co-resistance to non-beta lactam antibiotics was observed more with ESBL producers (P < 0.05). The results showed that the studied ESBL genes are found with high prevalence and among them blaCTX is more widespread in urine E. coli isolates in Mashhad.