VIM-2 Type Metallo-beta-lactamase Producing Achromobacter xylosoxidans subsp. xylosoxidans Isolated from Urine Specimens

ABSTRACT

BACKGROUND: The dissemination of metallo-beta-lactamase (MBL) producing gram-negative bacilli is of great concern because MBL can hydrolyze carbapenem. We report herein the infection by VIM-2 type MBL producing Achromobacter xylosoxidans subsp. xylosoxidans. MATERIALS AND METHODS: For seven A. xylosoxidans subsp. xylosoxidans with reduced imipenem susceptibility, the detection for MBL was performed using EDTA double disk synergy test (EDTA- DDS) and the PCR for IMP-1, VIM-1 and VIM-2 genes. The minimal inhibitory concentration (MIC) of MBL producers were determined by microbroth dilution methods. The DNA fingerprinting analysis was performed by random amplified polymorphic DNA. RESULTS: All seven isolates were MBL producers when tested with EDTA-DDS test and these isolates were VIM-2 type confirmed by the PCR and DNA sequencing analysis. The MIC against imipenem ranged from 16 to 32 microgram/mL in these isolates. The DNA fingerprints of these isolates were identical. CONCLUSION: A. xylosoxidans subsp. xylosoxidans manifest resistance against imipenem by acquisition of VIM-2 type MBL. To our knowledge, this is the first report on the VIM-2 type MBL producing A. xylosoxidans subsp. xylosoxidans.