Department of Infectious Diseases, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku, Tokyo 162-8655, Japan.
Int J Antimicrob Agents. 2012 Jun;39(6):518-21. doi: 10.1016/j.ijantimicag.2012.01.020. Epub 2012 Apr 5.
The emergence of multidrug-resistant (MDR) Pseudomonas aeruginosa isolates producing IMP-type metallo-β-lactamases (MBLs) and aminoglycoside 6'-N-acetyltransferase [AAC(6')-Iae] has become a serious problem in medical settings in Japan. A total of 217 MDR P. aeruginosa isolates were obtained from August 2009 to April 2010 from patients at 144 hospitals in Japan, of which 145 (66.8%) were positive for IMP-type MBLs and AAC(6')-Iae when tested with an immunochromatographic assay. Polymerase chain reaction (PCR) showed that these isolates were also positive for blaIMP and aac(6')-Iae genes. When these IMP-type MBL- and AAC(6')-Iae-producing isolates were analysed by pulsed-field gel electrophoresis (PFGE), two clusters (I and II) were detected. Most of the isolates (88.3%; 128/145) were grouped under cluster I and had multilocus sequence type ST235 and serotype O11, except for one isolate that was ST991 and serotype O3. The isolates were mainly isolated from the urinary tract (82/145; 56.6%) and respiratory tract (58/145; 40.0%). The epidemiological properties of the isolates belonging to cluster I were similar to those of MDR P. aeruginosa isolates that have been previously reported in Japan. The remaining 16 isolates belonged to cluster II, had identical PFGE patterns and were multilocus sequence type ST991 and serotype O18; all of these isolates were isolated from the respiratory tract. The properties of isolates belonging to cluster II have not been previously described, indicating that a novel IMP-type MBL- and AAC(6')-Iae producing P. aeruginosa strain is emerging in Japan. Isolates belonging to both clusters were isolated from different parts of the country.
在日本的医疗机构中，出现了多重耐药（MDR）铜绿假单胞菌分离株，这些分离株产生 IMP 型金属β-内酰胺酶（MBLs）和氨基糖苷 6'-N-乙酰转移酶 [AAC(6')-Iae]，这已成为一个严重的问题。2009 年 8 月至 2010 年 4 月，从日本 144 家医院的患者中获得了 217 株 MDR 铜绿假单胞菌分离株，其中 145 株（66.8%）经免疫层析法检测呈 IMP 型 MBL 和 AAC(6')-Iae 阳性。聚合酶链反应（PCR）显示这些分离株也呈 blaIMP 和 aac(6')-Iae 基因阳性。通过脉冲场凝胶电泳（PFGE）对这些产 IMP 型 MBL 和 AAC(6')-Iae 的分离株进行分析，检测到两个聚类（I 和 II）。大多数分离株（88.3%；128/145）归属于聚类 I，具有多位点序列型 ST235 和血清型 O11，除了一个分离株为 ST991 和血清型 O3。这些分离株主要从泌尿道（82/145；56.6%）和呼吸道（58/145；40.0%）分离。属于聚类 I 的分离株的流行病学特性与日本先前报道的 MDR 铜绿假单胞菌分离株相似。其余 16 株属于聚类 II，具有相同的 PFGE 模式，为多位点序列型 ST991 和血清型 O18；所有这些分离株均从呼吸道分离。属于聚类 II 的分离株的特性以前没有描述过，这表明一种新型的 IMP 型 MBL 和 AAC(6')-Iae 产生的铜绿假单胞菌菌株正在日本出现。属于这两个聚类的分离株来自日本不同地区。
