Prevalence of extended-spectrum β-lactamases and characterization of integron class 1 in extended spectrum β lactamase-producing klebsiella pneumoniae in sina hospital, Tabriz 2012

The existence of beta-lactmase among gram-negative bacteria such as Klebsiella pneumoniae, as a significant pathogen in nosocomial infection is the most important cause of resistance against beta- lactam antibiotics family. Class 1 integrons are mobile genetic elements which are mostly prevalent in drug-resistant bacteria. This study was conducted to determine the prevalence of phenotypic and genotypic ESBL-producing strains as well as the incidence of integron class 1 in ESBL-producing strains.
Sixty three isolates of K.pneumoniae, confirmed by biochemical and phenotypic tests, were collected within six months. Susceptibility test was carried out by Disk diffusion method. Prevalence of ESBL producing strains were determined by using Combined Disk Test. Presence of bla TEM , bla SHV gene family and class I integron were detected by PCR technique.
Forty five (71.4%) of isolates were ESBL-producing .TEM and SHV gene family were existed in 66.6% and 68.9% of ESBL -producing isolates, respectively. Class I integron were detected in 24 (65%) and 19 (63.3%) of SHV and TEM positive strains, respectively.
In present study, increasing level of ESBL producing isolates were confirmed. Also, this study intensely demonstrates the role of integron in the dissemination of ESBL-mediated resistance among the nosocomial isolates .Overall, using the proper treatment procedure according to the antibiogram pattern of the strains is specifically recommended.