Epidemiology of Plasmid-Mediated AmpC beta-Lactamase Produced by Clinical Isolates of Klebsiella pneumoniae from Four University Hospitals in Korea.
- Author:
Wonkeun SONG
1
;
Jae Seok KIM
;
Chang Hoon LEE
;
Jongwook LEE
;
Kyungwon LEE
Author Information
1. Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, Korea. swonkeun@hallym.or.kr
- Publication Type:Original Article
- Keywords:
Plasmid-mediated AmpC beta-lactamase;
Klebsiella pneumoniae;
DHA-1
- MeSH:
Aztreonam;
beta-Lactamases*;
Cefoxitin;
Ceftazidime;
Chungcheongbuk-do;
Clone Cells;
Cross Infection;
Electrophoresis, Gel, Pulsed-Field;
Epidemiology*;
Hospitals, University*;
Imipenem;
Klebsiella pneumoniae*;
Klebsiella*;
Korea*;
Pneumonia;
Polymerase Chain Reaction;
Sequence Analysis, DNA
- From:Korean Journal of Nosocomial Infection Control
2007;12(2):103-111
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Plasmid-mediated AmpC beta-lactamases (PABLs) are cephalosporinases that confer resistance to a wide variety of beta-lactam drugs and that may thereby create serious therapeutic problems. The PABL-producing organisms are a major concern in nosocomial infections and should therefore be monitored in surveillance studies. METHODS: During the period of May to July 2004, 27 cefoxitin non-susceptible isolates of Klebsiella pneumoniae from four university hospitals (Seoul 2, Daejeon 1, and Choongju 1) were tested for antimicrobial susceptibility by the broth microdilution method. The cefoxitin non-susceptible isolates were further investigated by the double disk synergy test for extended-spectrum beta-lactamases, multiplex AmpC PCR, DNA sequencing, and pulsed-field gel electrophoresis (PFGE). RESULTS: PABL-producing K. pneumoniae were found in all the four hospitals. Eight (32%) of 25 PABL producers were also tested positive by double disk synergy tests. Susceptibilities of the PABL producers were as follows: ceftazidime, 4%; aztreonam, 36%; cefepime, 76%; and imipenem, 100%. Among the 25 K. pneumoniae isolates were 24 DHA-1 and 1 CMY-1 beta-lactamase producers. The PFGE patterns of the DHA-1-producing K. pneumoniae showed variable as well as identical patterns. CONCLUSION: PABL-producing K. pneumoniae is widespread among medical institutions in Korea. A DHA-1 type in K. pneumoniae was the predominant enzyme detected. Overall, despite many different PFGE patterns of the PABL producers, some outbreak and epidemic clones appear to be prevalent in some hospitals in Korea. For the prevention of the spread of PABL-producing K. pneumoniae, it should be identified accurately by the clinical laboratory.
