Molecular characteristics of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae causing intra-abdominal infections from 9 tertiary hospitals in China
单位：[1]Department of Laboratory Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China东院检验科中山大学附属第一医院[2]Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing 100730, China[3]Ruijin Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200025, China[4]SirRunRun Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou 310016, China[5]Zhong Shan Hospital of Fu Dan University, Shanghai 200032, China[6]Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology,Wuhan 430030, China华中科技大学同济医学院附属同济医院[7]First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China重庆医科大学附属第一医院[8]Shandong Provincial Hospital Affiliated to Shandong University, Jinan 250021, China[9]Xiangya Hospital, Central Southern University, Changsha 410008, China[10]First Affiliated Hospital of Zhengzhou University, Zhenzhou 450052, China[11]The General Hospital of People's Liberation Army, Beijing 100853, China[12]General Hospital of Tianjin Medical University, Tianjing 300052, China[13]First Affiliated Hospital of Chinese Medical University, Shenyang 110001, China[14]First Affiliated Hospital of Haerbin Medical College, Haerbin 150081, China[15]Chaoyang Hospital of Capital Medical College, Beijing 100020, China北京朝阳医院[16]Friendship Hospital of Capital Medical College, Beijing 100020, China首都医科大学附属北京友谊医院[17]Second Affiliated Hospital of Nanchang University, Nanchang 330006, China[18]People's Hospital of Jilin Province, Jilin 130021, China[19]People's Hospital of Haikou City, Haikou 570208, China[20]General Hospital of Nanjing Military Command, Nanjing 210002, China[21]First Affiliated Hospital of Zhejiang University, Hangzhou 310003, China浙江大学医学院附属第一医院
Background: Recently, the emergence of multidrug-resistant organisms such as extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae has raised considerable concern regarding the appropriate treatment of intra-abdominal infections (Yds). In this study, we investigated the molecular characteristics of ESBL among clinical isolates of Escherichia coli and Klebsiella pneumoniae causing lAls and their pattern of antimicrobial resistance, which can provide useful information about the epidemiology and risk factors associated with these infections. Materials and methods: One hundred sixty-seven E.co li and 47 K. pneumoniae ESBL-producing strains causing IAIs were collected from 9 hospitals in China, during 2012 and 2013. The antimicrobial susceptibility profile of these strains was determined. Polymerase chain reaction and sequencing were performed to identify genes for beta-lactamase (bIaTEM, b1aSHV, blaOXA-1-like, and blaCTX-M). The isolates were also analyzed by pulsed-field gel electrophoresis (PFGE). Results: In 167 ESBL-producing E. coli strains, 104 strains (623%) were positive for CTX-M, and 9 strains (5.39%) were positive for SHV. Among the 47 K. pneumoniae strains, 35 strains (74.5%) were positive for SHV-2a, 12 strains (25.5%) were positive for CTX-M. No TEM-type and OXA-1-like strain was detected among all the ESBL-producing strains. Regarding the CTX-M-positive E. coli and K. pneumoniae strains, CFX-M-15 was the most common genotype in E. coli and K. pneumoniae strains, accounting for 28.7% and 17.0%, respectively, followed by CTX-M-55 accounting for 16.2% and 2.13%, respectively; the remaining genotypes included CTX-M-123 and CTX-M-82. PFGE showed that E.coli and K. pneumoniae ESBL-producing strains causing lAls were diverse and that emerging resistance may not be due to the dissemination of national clones. Conclusion: The present study revealed that in ESBL-producing strains causing IAIs in China, the most common genotype for E.coli was CTX-M-15 and for K. pneumoniae was SHV-2a. However, there was a wide diversity of strains causing 'Ms among the ESBL-producing E. coll. and K. pneumoniae. (C) 2016 Elsevier Inc. All rights reserved.
基金：
Merck Sharp Dohme (MSD; Whitehouse Station, NJ); MSD China
