Fukigai Shinako, Alba Jimena, Kimura Soichiro, Iida Toshie, Nishikura Noriko, Ishii Yoshikazu, Yamaguchi Keizo
Division of Microbiology, Department of Clinical Laboratory, Hanyu General Hospital, Saitama, Japan.
Int J Antimicrob Agents. 2007 Mar;29(3):306-10. doi: 10.1016/j.ijantimicag.2006.10.011. Epub 2007 Feb 2.
Gram-negative bacteria with acquired metallo-beta-lactamase (MBL) resistance are being increasingly described worldwide. Here we report the first case of an outbreak by a cluster of genetically related strains of Klebsiella pneumoniae producing the IMP-1 MBL. Six isolates of K. pneumoniae with a ceftazidime minimum inhibitory concentration >/=64 microg/mL were collected between February 2003 and June 2004 in Hanyu General Hospital, Saitama, Japan. These isolates were analysed to establish the mechanism of resistance. The zone of inhibition of these isolates using ceftazidime or imipenem disks on Mueller-Hinton agar containing dipicolinic acid was much larger than on Mueller-Hinton agar without dipicolinic acid. Polymerase chain reaction and DNA sequencing confirmed that the isolates contained bla(IMP-1) as well as intI1 as a class I integrase gene. Pulsed-field gel electrophoresis was performed, showing that five of the six isolates were related. This outbreak was controlled by restrained and careful use of antibiotics as well as strict hygiene practices.
在全球范围内，具有获得性金属β-内酰胺酶（MBL）耐药性的革兰氏阴性菌越来越多地被发现。在此，我们报告首例由一群产生IMP-1 MBL的基因相关肺炎克雷伯菌菌株引起的暴发。2003年2月至2004年6月期间，在日本埼玉县羽生综合医院收集了6株头孢他啶最低抑菌浓度≥64μg/mL的肺炎克雷伯菌分离株。对这些分离株进行分析以确定其耐药机制。在含有吡啶二羧酸的穆勒-欣顿琼脂上，使用头孢他啶或亚胺培南纸片对这些分离株进行抑菌圈试验，其抑菌圈比在不含吡啶二羧酸的穆勒-欣顿琼脂上大得多。聚合酶链反应和DNA测序证实，这些分离株含有bla(IMP-1)以及作为I类整合酶基因的intI1。进行了脉冲场凝胶电泳，结果显示6株分离株中有5株具有相关性。通过限制和谨慎使用抗生素以及严格的卫生措施，此次暴发得到了控制。
