MLST analysis of multiple antimicrobial resistant Acinetobacter baumannii
Tsutomu Yasuhara1, Satoshi Kugawa, Yuko Tateishi
1Department of Pathology, Division of Diagnostic Pathology and Laboratory Medicine, Tokyo 142 8666.
Rinsho Byori. the Japanese Journal of Clinical Pathology
|August 17, 2013
Summary
Multi-locus sequencing typing identified the global epidemic clone, Clonal Complex 92 Acinetobacter baumannii, in Japanese hospitals. This carbapenem-resistant strain highlights the need for ongoing molecular surveillance of Acinetobacter baumannii.
Area of Science:
- Medical Microbiology
- Molecular Epidemiology
Background:
- Acinetobacter baumannii is a significant nosocomial pathogen.
- Carbapenem resistance in A. baumannii poses a global health threat.
Observation:
- Multi-locus sequencing typing (MLST) was performed on 15 Acinetobacter baumannii isolates from Showa University Hospital (Nov 2010-Mar 2011).
- Three isolates were identified as Sequence Types (STs) 76, 92, and 146, all belonging to Clonal Complex (CC) 92.
- The remaining 12 strains were not classifiable by MLST.
Findings:
- ST76, ST92, and ST146 strains exhibited resistance to various antibiotics, including carbapenems, aminoglycosides, and fluoroquinolones.
- Notably, carbapenem-resistant isolates lacked common carbapenemase genes (IMP, VIM2, OXA23).
- CC92 strains demonstrated significant drug resistance, while other strains were susceptible.
Implications:
- The findings suggest the spread of drug-resistant Acinetobacter baumannii, specifically CC92, in Japan.
- Molecular epidemiology is crucial for monitoring and controlling the dissemination of resistant strains.
- The absence of specific resistance genes warrants further investigation into resistance mechanisms.
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