In vitro activities and detection performances of cefmetazole and flomoxef for extended-spectrum β-lactamase and plasmid-mediated AmpC β-lactamase-producing Enterobacteriaceae

Yasufumi Matsumura; Masaki Yamamoto; Miki Nagao; Michio Tanaka; Shunji Takakura; Satoshi Ichiyama

doi:10.1016/j.diagmicrobio.2015.12.001

In vitro activities and detection performances of cefmetazole and flomoxef for extended-spectrum β-lactamase and plasmid-mediated AmpC β-lactamase-producing Enterobacteriaceae

Diagn Microbiol Infect Dis. 2016 Apr;84(4):322-7. doi: 10.1016/j.diagmicrobio.2015.12.001. Epub 2015 Dec 11.

Authors

Yasufumi Matsumura¹, Masaki Yamamoto², Miki Nagao³, Michio Tanaka⁴, Shunji Takakura⁵, Satoshi Ichiyama⁶

Affiliations

¹ Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: yazblood@kuhp.kyoto-u.ac.jp.
² Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: masakiy@kuhp.kyoto-u.ac.jp.
³ Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: mnagao@kuhp.kyoto-u.ac.jp.
⁴ Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: mbac@kuhp.kyoto-u.ac.jp.
⁵ Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: stakakr@kuhp.kyoto-u.ac.jp.
⁶ Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: sichiyam@kuhp.kyoto-u.ac.jp.

PMID: 26782634
DOI: 10.1016/j.diagmicrobio.2015.12.001

Abstract

To investigate the in vitro activities of cephamycins (cefmetazole and flomoxef) for extended-spectrum β-lactamase (ESBL)- and plasmid-mediated AmpC β-lactamase (pAmpC)-producing Enterobacteriaceae, a total of 574 third-generation cephalosporin-resistant clinical isolates were collected at a Japanese multicenter study. PCR and sequencing identified 394 isolates with only ESBL genes, 63 isolates with only pAmpC genes, and 6 isolates with both ESBL and pAmpC genes. blaCTX-M types predominated 95.5% of the ESBL genes, and blaCMY-2 predominated 91.3% of the pAmpC genes. The MIC50/90 values of cefmetazole and flomoxef were ≤ 1/4 and ≤ 1/≤ 1 μg/mL for isolates with only ESBL genes, respectively, and 16/>16 and 8/16 μg/mL for isolates with only pAmpC genes, respectively. Flomoxef ≥ 4 μg/mL had the best screening performance for the detection of isolates with pAmpC genes. Flomoxef had better in vitro activities against ESBL-producing Enterobacteriaceae and provided a clearer distinction between ESBL and pAmpC-producing Enterobacteriaceae compared to cefmetazole.

Keywords: AmpC; Cephamycin; ESBLs; Genotype; MIC.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Anti-Bacterial Agents / pharmacology*
Cefmetazole / pharmacology*
Cephalosporins / pharmacology*
Enterobacteriaceae / classification
Enterobacteriaceae / drug effects*
Enterobacteriaceae / enzymology*
Enterobacteriaceae / genetics
Enterobacteriaceae Infections / microbiology
Genotype
Humans
Japan
Microbial Sensitivity Tests
Polymerase Chain Reaction
Sequence Analysis, DNA
beta-Lactam Resistance*
beta-Lactamases / metabolism*

Substances

Anti-Bacterial Agents
Cephalosporins
Cefmetazole
beta-Lactamases
flomoxef