Background: The dissemination of extended-spectrum β-lactamases (ESBL) in Klebsiella pneumoniae isolates has resulted in the increase of antibiotic resistance and mortality among patients. The aim of this study was to determine the prevalence of ESBL and SHV-2a, SHV-5 and SHV-12 genes in K. pneumoniae isolates from Kermanshah.

Materials and Methods: In this descriptive – analytical study, from 112 clinical samples of patients admitted at Kermanshah medical centers in 2014, 60 K. pneumoniae isolates were recognized by standard methods of bacteriology and API Kit. Antibiotic susceptibility of isolates was determined by disk diffusion method and the isolates were screened for ESBL-producerig using the combination disc method. The SHV-2a, SHV-5 and SHV-12 genes were determined among isolates using PCR method. Primers were designed in this study.

Results: Of 60 isolates tested, the highest and the lowest resistance was for ampicillin and carbapenem antibiotics, respectively. Forty-five percent of isolates were ESBL-producer. Among 60 isolates tested, 5 (8.3%), 57 (95%) and 43 (71.7%) isolates contained SHV-2a, SHV-5 and SHV-12 genes, respectively. Five isolates contained all the three genes of SHV-2a, SHV-5 and SHV-12.

Conclusion: The results indicate the relatively high prevalence of SHV type beta-lactamase genes in K. pneumoniae isolates in Kermanshah. Given this high prevalence, the surveillance of antibiotic resistant patterns and relevant genes is necessary among gram-negative bacilli in Kermanshah region. Due to the high resistance of K. pneumoniae isolates to antibiotics and to reduce the dissemination of resistant genes, susceptibility testing to choose more affective antibiotics is recommended even for isolates from outpatients.

Background: The efflux pumps are one of the main mechanisms of resistance to antibiotics in E. coli and K. pneumoniae strains. The aim of this study is to study the association between genes coding efflux pumps AcrAB and Qep A and ciprofloxacin resistance among E. coli and K. pneumoniae clinical strains

Materials and Methods: This study was done on 100 strains of E. coli isolated from Taleghani and Labbafinejad Hospitals and 100 strains of K. pneumoniae isolated from Taleghani and Mofid Children Hospitals. Antimicrobial susceptibility tests were performed by disk diffusion method based on CLSI guidelines. Identification of genes encoding efflux pumps Acr AB and Qep A was done by PCR technique.

Results: In this study, fosfomycin and imipenem had the best effect against E. coli clinical isolates and fosfomycin and tigecycline had the best effect against K. pneumoniae clinical isolates. PCR assay demonstrated that the prevalence of AcrA, AcrB and QepA genes among E. coli isolates were 92%, 84% and 0%, respectively and among K. pneumoniae isolates were 94%, 87% and 4%, respectively.

Conclusion: The prevalence of genes encoding efflux pumps in E. coli and K. pneumoniae clinical strains, which causes resistance to fluoroquinolones, is cause for concern. Therefore, controlling infection and preventing the spread of drug-resistant bacteria needs to manage medication carefully and identify resistant isolates.