title: Distribution of carbapenem resistance determinants among epidemic and non-epidemic types of Acinetobacter species in Japan.
abstract: We performed a comparative molecular analysis on three types of clinically isolated Acinetobacter spp.: epidemic sequence types (STs) of Acinetobacter baumannii (epidemic ST-AB), non-epidemic sequence types of A. baumannii (non-epidemic ST-AB) and non-baumannii Acinetobacter spp. A total of 87 isolates - 46 A. baumannii, 25 A. pittii and 16 A. nosocomialis - from 43 hospitals were analysed. Of these, 31 A. baumannii isolates were ST1 or ST2 according to the Pasteur Institute multilocus sequence typing scheme and were defined as epidemic ST-AB. The other 15 A. baumannii isolates were defined as non-epidemic ST-AB. The epidemic ST-AB isolates harboured the blaOXA-23-like gene or had an ISAba1 element upstream of blaOXA-51-like, or both, whereas non-epidemic ST-AB and non-baumannii Acinetobacter spp. isolates harboured blaOXA-58-like or metallo-β-lactamase genes, or both. The proportion of multidrug-resistant isolates was significantly higher in the epidemic ST-AB isolates (48 %) than that in the other types of Acinetobacter isolates (5 %) (P<0.05). In addition, epidemic ST-AB isolates exhibited a relatively higher proportion of fluoroquinolone resistance. We demonstrated that, in terms of genotypes and phenotypes of antimicrobial resistance, non-epidemic ST-AB isolates shared more similarity with non-baumannii Acinetobacter spp. isolates than with epidemic ST-AB isolates, regardless of bacterial species. In addition, this study revealed that, even in Japan, where IMP-type metallo-β-lactamase producers are endemic, epidemic ST-AB harbouring blaIMP have not yet emerged.
authors.affiliation: Department of Bacteriology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashi-Murayama, Tokyo 208-0011, Japan.
authors.forename: Mari
authors.initials: M
authors.lastname: Matsui
authors.affiliation: Department of Bacteriology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashi-Murayama, Tokyo 208-0011, Japan.
authors.forename: Satowa
authors.initials: S
authors.lastname: Suzuki
authors.affiliation: Department of Public Health, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama 701-0192, Japan.|Department of Bacteriology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashi-Murayama, Tokyo 208-0011, Japan.
authors.forename: Kunikazu
authors.initials: K
authors.lastname: Yamane
authors.affiliation: Department of Bacteriology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashi-Murayama, Tokyo 208-0011, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Department of Bacteriology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashi-Murayama, Tokyo 208-0011, Japan.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Konda
authors.affiliation: Department of Bacteriology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan.|Department of Bacteriology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashi-Murayama, Tokyo 208-0011, Japan.
authors.forename: Yoshichika
authors.initials: Y
authors.lastname: Arakawa
authors.affiliation: Department of Bacteriology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashi-Murayama, Tokyo 208-0011, Japan.
authors.forename: Keigo
authors.initials: K
authors.lastname: Shibayama
mesh_terms: D000150:Acinetobacter / Q000145:classification* / Q000201:enzymology; D000151:Acinetobacter Infections / Q000453:epidemiology / Q000382:microbiology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D015780:Carbapenems / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D006801:Humans; D007564:Japan / Q000453:epidemiology; D058885:Multilocus Sequence Typing; D013045:Species Specificity; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D015780:Carbapenems; D001618:beta-Lactamases; C063912:carbapenemase