Journal List > J Bacteriol Virol > v.46(4) > 1034224

J Bacteriol Virol. 2016 Dec;46(4):213-220. Korean.
Published online December 31, 2016.
Copyright © 2016 The Korean Society for Microbiology and The Korean Society of Virology
Antimicrobial Susceptibility and Clonal Distribution of the Blood Isolates of Pseudomonas aeruginosa from Two Korean Hospitals
Chi Hyun Kim and Je Chul Lee
Department of Microbiology, Kyungpook National University School of Medicine, Daegu, Korea.

Corresponding author: Je Chul Lee. Department of Microbiology, Kyungpook National University School of Medicine, 680 Gukchaebosang-ro, Jung-gu, Daegu 41944, Korea. Phone: +82-53-420-4844, Fax: +82-53-427-5664, Email:
Received November 10, 2013; Revised November 27, 2016; Accepted December 01, 2016.

This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (


An increasing prevalence of infections caused by multidrug-resistant (MDR) Pseudomonas aeruginosa (P. aeruginosa) causes a serious therapeutic problem in clinical setting. This study investigated the antimicrobial susceptibility, resistance mechanisms against aminoglycosides, and molecular epidemiology of 76 blood isolates of P. aeruginosa from two Korean hospitals. Thirty-four isolates were susceptible to all 13 antimicrobial agents tested, whereas 28 isolates showed a MDR or extensively drug-resistant phenotype. There was a significant difference in resistance rates of P. aeruginosa isolates against aztreonam, piperacillin-tazobactam, imipenem, meropenem, ciprofloxacin, and norfloxacin between two hospitals. Genes for aminoglycoside-modifying enzymes (AMEs), including aphA6 (n = 14), aadB (n = 11), aacA4 (n = 8), and aphA1 (n = 1), and 16S rRNA methylase armA (n = 6) were detected in 26 P. aeruginosa isolates resistant to aminoglycosides. There was no significant difference in carriage of genes for AME and 16S rRNA methylase between two hospitals, but aacA4 and aphA1 were specifically detected in P. aeruginosa isolates from one hospital. Seventy-six P. aeruginosa isolates were classified into 55 pulsotypes at similarity value of 0.85, and 31 and 24 pulsotypes were specifically detected in each hospital. This study demonstrates that differences in antimicrobial susceptibility of P. aeruginosa isolates between two hospitals are possibly due to the presence of diverse clones specific in each hospital.

Keywords: P. aeruginosa; Antimicrobial agent; Resistance; Aminoglycoside; 16S rRNA methylase


Figure 1
Pulsed-field gel electrophoresis analysis of 76 P. aeruginosa isolates from two Korean hospitals. Dendrogram showing a clustering of SpeI-generated PFGE patterns from P. aeruginosa isolates. Abbreviations: KNUH, Hospital A; CNUH, hospital B.
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Table 1
PCR primers used in this study
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Table 2
Antimicrobial susceptibility of P. aeruginosa isolates from two Korean hospitals
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Table 3
Antimicrobial susceptibility profiles that fit MDR, XDR, and PDR for 76 P. aeruginosa isolates
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Table 4
Detection of resistant determinants for aminoglycosides in P. aeruginosa isolates from two Korean hospitals
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