Evaluation of antibiotic susceptibility pattern and frequency of blaTEM and blaSHV genes in hospital isolates of Klebsiella pneumoniae

Nowadays, one of the major problems in microbial infection treatments, is the antibiotic resistant bacteria. The Klebsiella pneumoniae is resistant against many of the antibiotics because of producing beta-lactamase enzymes. The aim of this study is to evaluate the resistance of K. pneumoniae against antibiotics and also to determine the frequency of beta-lactamase genes blaTEM and blaSHV. ۱۰۰ isolates of K. pneumonia from urine samples were collected and confirmed. Antibiotic resistance pattern was studied by disk diffusion method and ESBLproducing isolates were identified in two stages including primary screening and phenotypic confirmatory tests. PCR method was used to study the frequency of blaTEM and blaSHV genes. Results showed that the lowest antibiotic resistance of isolates was to amikacin (۳۲%) and the highest resistance was to amoxicillin, amoxicillin-clavulanic acid, cefalexin and cefalotin, so that all isolates were resistant to them. Finally from ۲۳ samples of ESBL producing K. pneumoniae, ۱۸ samples (۷۸.۲۷%) presented blaTEM and ۲۱ samples (۹۱.۳%) presented blaSHV genes. Overall, the determination of the antibiotic susceptibility and identification of beta-lactamase genes in ESBLs producing bacteria would help to choose the appropriate antimicrobial agents for treatments.

Keywords:

antibiotic resistant bacteria , betalactamase genes