Rapidly spreading CTX-M-type β-lactamase-producing Proteus mirabilis in Japan

Kanayama, Akiko; Iyoda, Takako; Matsuzaki, Kaoru; Saika, Takeshi; Ikeda, Fumiaki; Ishii, Yoshikazu; Yamaguchi, Keizo; Kobayashi, Intetsu

doi:10.1016/j.ijantimicag.2010.06.002

« Previous Next »International Journal of Antimicrobial Agents
Volume 36, Issue 4 , Pages 340-342, October 2010

Rapidly spreading CTX-M-type β-lactamase-producing Proteus mirabilis in Japan

Akiko Kanayama
- Department of Infection Control and Prevention, Faculty of Medicine, Toho University, 4-16-20, Omori-nishi, Ota-ku, Tokyo 143-0015, Japan
Takako Iyoda
- Chemotherapy Division, Mitsubishi Chemical Medience Corporation, 3-30-1, Shimura, Itabashi-ku, Tokyo 174-8555, Japan
Kaoru Matsuzaki
- Chemotherapy Division, Mitsubishi Chemical Medience Corporation, 3-30-1, Shimura, Itabashi-ku, Tokyo 174-8555, Japan
Takeshi Saika
- Chemotherapy Division, Mitsubishi Chemical Medience Corporation, 3-30-1, Shimura, Itabashi-ku, Tokyo 174-8555, Japan
Fumiaki Ikeda
- Chemotherapy Division, Mitsubishi Chemical Medience Corporation, 3-30-1, Shimura, Itabashi-ku, Tokyo 174-8555, Japan
Yoshikazu Ishii
- Department of Microbiology and Infectious Diseases, School of Medicine, Toho University, 5-21-16, Omori-nishi, Ota-ku, Tokyo 143-8540, Japan
Keizo Yamaguchi
- Department of Microbiology and Infectious Diseases, School of Medicine, Toho University, 5-21-16, Omori-nishi, Ota-ku, Tokyo 143-8540, Japan
Intetsu Kobayashi
- Department of Infection Control and Prevention, Faculty of Medicine, Toho University, 4-16-20, Omori-nishi, Ota-ku, Tokyo 143-0015, Japan
- Corresponding author. Tel.: +81 3 3762 9247; fax: +81 3 3762 9247.

Received 19 February 2010; accepted 2 June 2010. published online 08 July 2010.

Abstract

In recent years, increased isolation of extended-spectrum β-lactamase (ESBL)-producing Proteus mirabilis has been reported in Japan. We undertook an investigation to determine the prevalence of ESBL-producing P. mirabilis isolated in Japan and to characterise the genotype. Seventy-four P. mirabilis isolates recovered from specimens at 54 hospitals in Japan between March and October 2006 were included in the study. Of the 74 P. mirabilis isolates examined, 28 (37.8%) were ESBL-producers. The bla_CTX-M-2 gene was found in 27 isolates, whilst 1 isolate possessed bla_CTX-M-3. Amongst the 28 ESBL-producers, 25 (89.3%) were non-susceptible to ciprofloxacin, whilst 11 (23.9%) of 46 ESBL-non-producing isolates were non-susceptible to ciprofloxacin. Pulsed-field gel electrophoresis (PFGE) analysis of the 28 ESBL-producing isolates from 19 hospitals revealed 17 clusters. The same PFGE type was observed in two or more hospitals especially in the greater Tokyo area, suggesting possible clonal spread and the need for monitoring to determine whether emergence of a dominant clone occurs. Our results show that in Japan there is a high prevalence of CTX-M-type β-lactamase-producing P. mirabilis. Moreover, these isolates are characterised by reduced susceptibility to fluoroquinolones.

Keywords: CTX-M-type β-lactamase, Extended-spectrum β-lactamase, Proteus mirabilis