Dissemination Pattern of Multidrug Resistant Carbapenemase Producing Klebsiella pneumoniae Isolates Using Pulsed-Field Gel Electrophoresis in Southwestern Iran

BACKGROUND: Klebsiella pneumoniae is an important cause of healthcare-associated infection. Carbapenemases have increasingly been reported in Enterobacteriaceae, especially in K. pneumoniae. PROPOSE: The objective of this study was to determine antibiotic resistance patterns, and the molecular epidemiology of multidrug resistant K. pneumoniae isolates, obtained from hospitalized patients in Shiraz, Iran. METHODS: In this study, 60 K. pneumoniaeisolates were collected from Nemazee and Faghihi referral hospitals. Antibiotic susceptibility testing and MIC were performed by disk diffusion test and Epsilometer (E)-test strips, respectively. Carbapenemase genes were identified by polymerase chain reaction and sequencing. Then, clonal relationships were analyzed, using PFGE. RESULTS: Thirty-three out of 60 K. pneumoniae isolates were resistant to carbapenems. Among the isolates, 86.6% were multidrug resistant (MDR). Polymyxin B (18.3%) and tigecycline (23.3%) were shown to be the most active agents against K. pneumoniae isolates. In our study, the high prevalence of bla(NDM) (45%) and bla(OXA-48) (10%) was detected. CONCLUSION: The results of this study revealed the widespread carbapenemase gene between different wards in hospitals as a risk factor for treatment options. PFGE analysis showed 11 clusters and 3 singletons based on an 80% similarity level. Also, PFGE analysis showed that there were similar genetic patterns among K. pneumoniae isolates and these patterns were responsible for the distribution of infection in hospitals.