Fecal carriage of extended-spectrum β-lactamase-producing Enterobacteriaceae in hospital and community settings in Chad

Antimicrob Resist Infect Control. 2019 Oct 31:8:169. doi: 10.1186/s13756-019-0626-z. eCollection 2019.

Abstract

Background: Fecal carriage of extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE) remains poorly documented in Africa. The objective of this study was to determine the prevalence of ESBL-PE fecal carriage in Chad.

Methods: In total, 200 fresh stool samples were collected from 100 healthy community volunteers and 100 hospitalized patients from January to March 2017. After screening using ESBL-selective agar plates and species identification by MALDI-TOF mass spectrometry, antibiotic susceptibility was tested using the disk diffusion method, and ESBL production confirmed with the double-disc synergy test. The different ESBL genes in potential ESBL-producing isolates were detected by PCR and double stranded DNA sequencing. Escherichia coli phylogenetic groups were determined using a PCR-based method.

Results: ESBL-PE fecal carriage prevalence was 44.5% (51% among hospitalized patients vs 38% among healthy volunteers; p < 0.05). ESBL-producing isolates were mostly Escherichia coli (64/89) and Klebsiella pneumoniae (16/89). PCR and sequencing showed that 98.8% (87/89) of ESBL-PE harbored blaCTX-M genes: blaCTX-M-15 in 94.25% (82/87) and blaCTX-M-14 in 5.75% (5/87). Phylogroup determination by quadruplex PCR indicated that ESBL-producing E. coli isolates belonged to group A (n = 17; 27%), C (n = 17; 27%), B2 (n = 9; 14%), B1 (n = 8; 13%), D (n = 8; 13%), E (n = 1; 1.6%), and F (n = 1; 1.6%). The ST131 clone was identified in 100% (9/9) of E. coli B2 strains.

Conclusions: The high fecal carriage rate of ESBL-PE associated with CTX-M-15 in hospital and community settings of Chad highlights the risk for resistance transmission between non-pathogenic and pathogenic bacteria.

Keywords: Chad; ESBL; Enterobacteriaceae; Fecal carriage.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Anti-Bacterial Agents / pharmacology
  • Carrier State*
  • Chad / epidemiology
  • Child
  • Child, Preschool
  • Community-Acquired Infections*
  • Cross Infection*
  • Enterobacteriaceae / classification
  • Enterobacteriaceae / drug effects
  • Enterobacteriaceae / genetics*
  • Enterobacteriaceae Infections / epidemiology*
  • Enterobacteriaceae Infections / microbiology*
  • Feces / microbiology*
  • Female
  • Humans
  • Infant
  • Male
  • Microbial Sensitivity Tests
  • Middle Aged
  • Phylogeny
  • Public Health Surveillance
  • Young Adult
  • beta-Lactamases / biosynthesis
  • beta-Lactamases / genetics*

Substances

  • Anti-Bacterial Agents
  • beta-Lactamases