Nakama Rika, Shingaki Aoi, Miyazato Hiroko, Higa Rikako, Nagamoto Chota, Hamamoto Kouta, Ueda Shuhei, Hachiman Teruyuki, Touma Yuki, Miyagi Kazufumi, Kawahara Ryuji, Toyosato Takehiko, Hirai Itaru
Laboratory of Microbiology, School of Health Sciences, Faculty of Medicine, University of the Ryukyus, Nishihara, Okinawa 903-0215, Japan.
Okinawa Prefectural Nambu Medical Center & Children's Medical Center, Haebaru, Okinawa 901-1193, Japan.
J Infect Chemother. 2016 May;22(5):281-6. doi: 10.1016/j.jiac.2016.01.008. Epub 2016 Feb 15.
Enterobacteriaceae producing extended spectrum β-lactamase (ESBL) are distributed worldwide. In this study, 114 ESBL-producing Enterobacteriaceae were isolated by analyzing 1672 clinical isolates of Enterobacteriaceae collected from an Okinawa prefectural hospital in Japan between June 2013 and July 2014. The overall prevalence of ESBL-producing Enterobacteriaceae was 6.8%; the prevalence of different bacterial species among the ESBL-producing isolates was as follows: 11.5% Escherichia coli (90 of 783 isolates), 6.2% Klebsiella pneumoniae (19 of 307 isolates), and 11.1% Proteus mirabilis (5 of 45 isolates). The ESBL types blaCTX-M-1, -3, -15, -2, -14, -27, and mutants of blaSHV-1 were detected. Among them, blaCTX-M-15 (33.3%), blaCTX-M-14 (27.8%) and blaCTX-M-27 (33.3%) were dominant in the E. coli isolates, whereas a blaSHV mutant which possessed four mutations (Tyr7Phe, Leu35Gln, Gly238Ser and Glu240Lys) in the amino acid sequence of SHV-1 dominated in the K. pneumoniae isolates (11 of 19, 57.9%). The pandemic E. coli ST131 clone was found to constitute 3.3% of the overall examined isolates and 62.2% of the ESBL-producing E. coli isolates. Our results suggest that the genetic combination of blaCTX-M, and blaSHV and antibiotics-resistant profile were different from that in other regions such as other areas of Japan, Asia, Europe, and North America, especially in the ESBL-producing K. pneumoniae isolates and in the E. coli B2-O25b-ST131 isolates possessing blaCTX-M-15 (40.7% of the E. coli B2-O25b-ST131 isolates). Taken together, our results indicate that the ESBL-producing Enterobacteriaceae in Okinawa, Japan, might be of a unique nature.
产超广谱β-内酰胺酶（ESBL）的肠杆菌科细菌在全球范围内均有分布。在本研究中，通过分析2013年6月至2014年7月间从日本冲绳县一家医院收集的1672株肠杆菌科临床分离株，分离出了114株产ESBL的肠杆菌科细菌。产ESBL肠杆菌科细菌的总体患病率为6.8%；产ESBL分离株中不同细菌种类的患病率如下：大肠埃希菌为11.5%（783株分离株中的90株），肺炎克雷伯菌为6.2%（307株分离株中的19株），奇异变形杆菌为11.1%（45株分离株中的5株）。检测到ESBL类型blaCTX-M-1、-3、-15、-2、-14、-27以及blaSHV-1的突变体。其中，blaCTX-M-15（33.3%）、blaCTX-M-14（27.8%）和blaCTX-M-27（33.3%）在大肠埃希菌分离株中占主导地位，而在肺炎克雷伯菌分离株中（19株中的11株，57.9%），一种在SHV-1氨基酸序列中具有四个突变（Tyr7Phe、Leu35Gln、Gly238Ser和Glu240Lys）的blaSHV突变体占主导地位。发现大流行的大肠埃希菌ST131克隆占总体检测分离株的3.3%，占产ESBL大肠埃希菌分离株的62.2%。我们的结果表明，blaCTX-M和blaSHV的基因组合以及抗生素耐药谱与日本其他地区、亚洲、欧洲和北美的其他地区不同，尤其是在产ESBL的肺炎克雷伯菌分离株以及携带blaCTX-M-15的大肠埃希菌B2-O25b-ST131分离株中（占大肠埃希菌B2-O25b-ST131分离株的40.7%）。综上所述，我们的结果表明，日本冲绳产ESBL的肠杆菌科细菌可能具有独特的性质。
