Genetic detection of extended-spectrum beta-lactamase-containing Escherichia coli isolates and vancomycin-resistant enterococci in fecal samples of healthy children

Microb Drug Resist. 2009 Sep;15(3):211-6. doi: 10.1089/mdr.2009.0910.

Abstract

One hundred twelve fecal samples of healthy children were recovered in Portugal during October 2007 and February 2008 and were tested for extended-spectrum beta-lactamases (ESBLs) containing Escherichia coli isolates and vancomycin-resistant enterococci (VRE). Three of the 112 fecal samples (2.7%) harbored ESBL-positive E. coli isolates and the bla(CTX-M-1), bla(TEM-52), and bla(SHV-12) genes were identified in these isolates. The bla(TEM-52)-containing isolate showed a phenotype of multiresistance that included fluoroquinolones, tetracycline, trimethoprim-sulfamethoxazole, and chloramphenicol; sul1, sul3, and cmlA genes were detected in this isolate, in addition to two amino acid changes in GyrA (Ser83Leu + Asp87Asn) and one in ParC protein (Ser80Ile). The ESBL isolates corresponded to phylogroup A (one isolate), B1 (one isolate), and D (one isolate). vanA-containing Escherichia faecium isolates were detected in 13 of the 112 fecal samples (11.6%), and vanC-1 isolates were found in 2 samples. A diversity of resistance genes [(tet(M), tet(L), erm(B), aph(3')-IIIa, ant(6)-Ia, catA, and vat(E)] were found in VRE isolates. These results show that the intestinal tract of healthy children constitutes a reservoir of ESBL-containing E. coli and VRE isolates.

MeSH terms

  • Adolescent
  • Anti-Bacterial Agents / pharmacology
  • Child
  • Child, Preschool
  • Disease Reservoirs*
  • Enterococcus / drug effects
  • Enterococcus / enzymology
  • Enterococcus / genetics
  • Enterococcus / isolation & purification*
  • Escherichia coli / drug effects
  • Escherichia coli / enzymology
  • Escherichia coli / genetics
  • Escherichia coli / isolation & purification*
  • Feces / microbiology*
  • Genotype
  • Humans
  • Infant
  • Microbial Sensitivity Tests
  • Phenotype
  • Vancomycin Resistance*
  • beta-Lactamases / genetics*
  • beta-Lactamases / metabolism

Substances

  • Anti-Bacterial Agents
  • beta-Lactamases