Study on the antibiotic resistance of extended-spectrum β-lactamases (ESBLs)-producing Klebsiella pneumoniae and the pulsed-field gel electrophoresis (PFGE) typing

Objective The study was conducted to explore the antibiotic resistance and molecular epidemiological characteristics of ESBLs-producing Klebsiella pneumoniae. Methods The Kirby-Bauer disk diffusion test was conducted in 49 isolates of ESBLs-producing Klebsiella pneumoniae to determine their resistance to 19 kinds of antibacterial agents. Homology analysis was done using PFGE (Pulsed-field gel electrophoresis). Results The sensitivity of 49 ESBLs-producing Klebsiella pneumoniae isolates to meropenem and Imipenem was 100%, whereas various degrees of resistance to other 17 kinds of antibiotics were revealed in the study. Six different PFGE types (A-F) were found among the 49 isolates, most of them being type A (27 strains) , followed by type B (10 strains) and C(9 strains). There were 19 isolates associated with the intensive care unit (ICU), accounting for 38.8%. The epidemic strains spread over different wards. Conclusion ESBLs-producing Klebsiella pneumoniae were multiresistant, whereas their sensitivity to meropenem and Imipenem was 100%, which made both agents the first choice to control ESBLs-producing Klebsiella pneumoniae infections. Alternative administration could be adopted based on the results of drug sensitivity test. An ESBLs-producing Klebsiella pneumoniae epidemic was reported in the First Affiliated Hospital to Zhejiang University Medical College from Feb to Aug, 2006. ICU ward is the high incident region of ESBLs-producing Klebsiella pneumoniae infection. High isolation rates were found in general surgery, respiratory, comprehensive and cadre wards. Therefore, detection and control of relevant strains and associated infections should be enhanced in future.