Molecular characterization and antimicrobial susceptibilities of Clostridium difficile clinical isolates from Victoria, Australia

• Clostridium difficile is a nosocomial pathogen, with different strain types causing disease.
• We have generated a snap-shot of C. difficile strain types circulating in Victoria.
• The diversity of isolates in Victoria may differ from other parts of the world.
• Most strains were toxinotype 0, but toxinotypes V and VIII strains were also found.
• Strains were metronidazole and vancomycin sensitive; 2 were moxifloxacin resistant.

Some Australian strain types of Clostridium difficile appear unique, highlighting the global diversity of this bacterium. We examined recent and historic local isolates, finding predominantly toxinotype 0 strains, but also toxinotypes V and VIII. All isolates tested were susceptible to vancomycin and metronidazole, while moxifloxacin resistance was only detected in recent strains.