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

Int J Antimicrob Agents. 2010 Oct;36(4):340-2. doi: 10.1016/j.ijantimicag.2010.06.002. Epub 2010 Jul 7.

Abstract

In recent years, increased isolation of extended-spectrum beta-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 beta-lactamase-producing P. mirabilis. Moreover, these isolates are characterised by reduced susceptibility to fluoroquinolones.

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Typing Techniques
  • Ciprofloxacin / pharmacology
  • DNA, Bacterial / genetics
  • Drug Resistance, Bacterial*
  • Electrophoresis, Gel, Pulsed-Field
  • Humans
  • Japan / epidemiology
  • Microbial Sensitivity Tests
  • Molecular Epidemiology
  • Polymerase Chain Reaction
  • Prevalence
  • Proteus Infections / drug therapy
  • Proteus Infections / epidemiology
  • Proteus Infections / microbiology
  • Proteus Infections / transmission*
  • Proteus mirabilis / drug effects*
  • Proteus mirabilis / enzymology
  • Proteus mirabilis / genetics*
  • Quinolones / pharmacology
  • Sequence Analysis, DNA
  • Time Factors
  • beta-Lactamases / biosynthesis*
  • beta-Lactamases / genetics
  • beta-Lactams / pharmacology

Substances

  • Anti-Bacterial Agents
  • DNA, Bacterial
  • Quinolones
  • beta-Lactams
  • Ciprofloxacin
  • beta-Lactamases