Emergence of CTX-M-9 Extended-Spectrum beta-Lactamase-Producing Enterobacter cloacae Isolates.
- Author:
Yoo Rah HONG
1
;
Hoyen YU
;
Il Kwon BAE
;
Su Bong KWON
;
Seok Hoon JEONG
;
Hyun Joo KIM
;
Youn Hwa KIM
;
Sang Hee LEE
Author Information
1. Department of Pediatrics, Kosin University College of Medicine, Busan, Korea.
- Publication Type:Original Article
- Keywords:
Enterobacter cloacae;
SHV-12;
CTX-M-9;
Enterobacterial repetitive intergenic con-sensus;
Polymerase chain reaction
- MeSH:
Agar;
Anti-Bacterial Agents;
Aztreonam;
beta-Lactamases;
Busan;
Cefotaxime;
Ceftazidime;
Consensus;
Enterobacter cloacae*;
Enterobacter*;
Humans;
Korea;
Molecular Epidemiology;
Polymerase Chain Reaction;
Prevalence
- From:Korean Journal of Clinical Microbiology
2005;8(1):57-65
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: The aim of this study is to assess the prevalence and to investigate the molecular epidemiology of Ambler class A extended-spectrum beta-lactamase (ESBL)-producing Enterobacter cloacae isolates in a university hospital in Busan, Korea. METHODS: Non-duplicated clinical isolates of E.cloacae from patients admitted in Kosin University Gospel Hospital were collected during the period from January through September, 2003. ESBL-production was examined by the double-disk synergy test (DDST) and the transferability of cefotaxime-resistance by conjugation. MICs of beta-lactam antibiotics were determined by the agar dilution method and Ambler class A ESBL genes were searched by PCR amplification. Enterobacterial repetitive intergenic consensus (ERIC) PCR was performed to investigate epidemiological relationships among bla CTX-M-9 gene-carrying E.cloacae isolates. RESULTS: Antimicrobial resistance rates of E.cloacae isolates (n=148) to ceftazidime, cefotaxime, and aztreonam were 50.0%, 29.6%, and 48.0%, respectively. Among 50 E.cloacae isolates intermediate or resistant to more than one expanded-spectrum beta-lactam agent, 41 (27.7%) showed positive results in DDST; of these 41 isolates, 1 was found to carry bla TEM-52 gene, 16 carried bla SHV-12 gene, 4 bla CTX-M-9 gene, and 19 both bla SHV-12 and bla CTX-M-9 genes. The 23 E.cloacae isolates carrying bla CTX-M-9 gene showed 9 different profiles by ERIC PCR. CONCLUSION: ESBL-producing E.cloacae was not uncommon in a university hospital in Busan, Korea. The commonest types of ESBLs produced by E.cloacae isolates were SHV-12 and CTX-M-9. CTX-M-9 ESBL-producing E.cloacae isolates showed diverse ERIC-PCR profiles, indicating that they were not originated from a common source.
