The Frequency of Extended Spectrum β-Lactamase Genes of SHV-2a, SHV-5 and SHV-12 in Clinical Isolates of Klebsiella Pneumoniae Isolated from Kermanshah Medical Centers in 2014

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.
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.
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.
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.