Molecular Characteristics of Extended-Spectrum beta -Lactamases in Clinical Isolates of Enterobacteriaceae.
- Author:
Seong Geun HONG
1
;
Myungseo KANG
;
Jong Rak CHOI
;
Kyungwon LEE
;
Yunsop CHONG
;
Oh Hun KWON
Author Information
1. Department of Clinical Pathology, Pundang CHA General Hospital, College of Medicine, Pochon CHA University, Sungnam, Korea.
- Publication Type:Original Article
- Keywords:
beta-Lactamase;
Enterobacteriaceae;
ESBL;
TEM;
SHV
- MeSH:
Base Sequence;
beta-Lactamases;
Citrobacter;
Citrobacter freundii;
Cloaca;
Enterobacter;
Enterobacter cloacae;
Enterobacteriaceae*;
Escherichia coli;
Humans;
Isoelectric Focusing;
Klebsiella pneumoniae;
Korea;
Mass Screening;
Pneumonia;
Polymerase Chain Reaction;
Prevalence;
Sequence Analysis, DNA;
Sequence Analysis, Protein;
Serratia;
Serratia marcescens
- From:Korean Journal of Clinical Pathology
2001;21(6):495-504
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: No significant information on the prevalence of extended-spectrum beta-Lactamase (ESBL)-producing Enterobacteriaceae in Korea has been available, because a few studies conducted to date in Korea have involved only discontinuous isolates of Klebsiella pneumoniae and Escherichia coli. In this study, a survey of clinical isolates of Enterobacteriaceae was carried out to assess the prevalence of ESBL-producing Enterobacteriaceae and to investigate the ESBL derivatives for phenotypical and genotypical characteristics. METHODS: A total of 500 consecutive clinical isolates of Enterobacteriaceae were screened for the presence of ESBL according to the new guidelines of the National Committee for Clinical Laboratory Standards. A double-disk synergy test, as a confirmatory test, was performed in screening positive strains. The presence of the ESBL gene was determined using polymerase chain reaction (PCR). The types of the beta-Lactamase gene were determined by isoelectric focusing and nucleotide sequence analysis. RESULTS: Among the collected strains, 21 of 293 E. coli (7.2%), 46 of 108 K. pneumoniae (42.6%), 10 of 20 Enterobacter cloacae (50.0%), 1 of 12 E. aerogenes (8.3%), 12 of 16 Citrobacter freundii (75.5%), and 1 of 14 Serratia marcescens (7.2%) were ESBL-producing strains. DNA sequencing and deduced amino acid sequence analysis revealed TEM-52 specific mutations in five strains (1 E. coli, 3 K. pneumoniae, and 1 E. cloacae) expressing pI 6.0 beta-Lactamases, SHV-2a in two K. pneumoniae of pI 7.6, and SHV-12 in four strains (1 E. coli of pI 8.2, 1 K. pneumoniae of pI 7.8, and 2 K. pneumoniae of pI 8.4). CONCLUSION: ESBLs were present in other genera of the family Enterobacteriaceae, such as Enterobacter, Citrobacter, and Serratia in Korea. ESBL types in E. coli isolates were TEM-52, SHV-12, and SHV-2a in decreasing order, and in K. pneumoniae isolates were TEM-52, SHV-2a and SHV-12 in decreasing order. The pIs of SHV-12 were 8.4 and 7.8 as well as 8.2, and a TEM-52 producing E. cloacae was first found.
