Epidemiology, Antimicrobial Resistance and beta-lactamase Genotypic Features of Enteropathogenic Escherichia coli Isolated from Children with Diarrhea in Southern China

作者：Huang Yong; Shan Xue feng; Deng Haijun; Huang Yu jun; Mu Xiao ping; Huang Ai long; Long Quan xin^*

来源：Japanese Journal of Infectious Diseases, 2015, 68(3): 239-243.

DOI：10.7883/yoken.JJID.2014.120

The main objective of this study was to investigate the epidemiology, drug resistance and beta-lactamase genotype distribution of enteropathogenic Escherichia coli (EPEC) isolated from pediatric patients with diarrhea in southern China. The prevalence of EPEC in children with diarrhea was 3.53%. The commonest serotypes were O55:K59 and O126:K71, and the typical EPEC were more prevalent than atypical EPEC (51 vs 7). Isolates from this region were most commonly found to be resistant to ampicillin and cotrimoxazole, followed by chloramphenicol, ceftriaxone, and ceftazidime. More than 96% of the strains were susceptible to cefoperazone/sulbactam and imipenem. The most common beta-lactamase genotypes identified in 58 strains were bLa(CTX-M-1) (60.3%), bla(TEM) (56.9%), bla(CTX-M-9) (27.6%), and bla(SHV) (15.5%). Among 58 isolates, 22 strains were found to harbor one beta-lactamase gene, and the proportions of resistance to ampicillin, cotrimoxazole, chloramphenicol, ceftriaxone, and ceftazidime, were 81.8%, 63.6%, 40.9%, 18.2%, and 9.1%, respectively. A further 30 strains carrying multiple beta-lactamase genes had increased resistance to the above antimicrobial agents (100%, 83.3%, 70.0%, 60.0%, and 30.0%, respectively). In contrast, antibiotic resistance in the last 6 strains without a detectable beta-lactamase gene was substantially reduced. Drug resistance may be associated with the beta-lactamase gene number, with a greater the number of beta-lactamase genes resulting in higher antibiotic resistance.

• 单位
  1; 重庆医科大学; 2