Antimicrobial susceptibility and emerging resistance determinants (blaCTX-M, rmtB, fosA3) in clinical isolates from urinary tract infections in the Bolivian Chaco

Int J Infect Dis. 2016 Feb:43:1-6. doi: 10.1016/j.ijid.2015.12.008. Epub 2015 Dec 11.

Abstract

Background: Bolivia is among the lowest-resourced South American countries, with very few data available on antibiotic resistance in bacterial pathogens. The phenotypic and molecular characterization of bacterial isolates responsible for urinary tract infections (UTIs) in the Bolivian Chaco are reported here.

Methods: All clinical isolates from UTIs collected in the Hospital Basico Villa Montes between June 2010 and January 2014 were analyzed (N=213). Characterization included susceptibility testing, extended-spectrum beta-lactamase (ESBL) detection, identification of relevant resistance determinants (e.g., CTX-M-type ESBLs, 16S rRNA methyltransferases, glutathione S-transferases), and genotyping of CTX-M producers.

Results: Very high resistance rates were observed. Overall, the lowest susceptibility was observed for trimethoprim-sulphamethoxazole, tetracycline, nalidixic acid, amoxicillin-clavulanic acid, ciprofloxacin, and gentamicin. Of E. coli and K. pneumoniae, 11.6% were ESBL producers. Resistance to nitrofurantoin, amikacin, and fosfomycin remained low, and susceptibility to carbapenems was fully preserved. CTX-M-15 was the dominant CTX-M variant. Four E. coli ST131 (two being H30-Rx) were identified. Of note, isolates harbouring rmtB and fosA3 were detected.

Conclusions: Bolivia is not an exception to the very high resistance burden affecting many South American countries. Optimization of alternative approaches to monitor local antibiotic resistance trends in resource-limited settings is strongly encouraged to support the implementation of effective empiric treatment guidelines.

Keywords: Bolivia; CTX-M; FosA3; RmtB; ST131; Urinary tract infections.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amoxicillin-Potassium Clavulanate Combination / therapeutic use*
  • Anti-Bacterial Agents / therapeutic use*
  • Bolivia / epidemiology
  • Drug Resistance, Bacterial / drug effects*
  • Drug Resistance, Bacterial / genetics
  • Escherichia coli / isolation & purification*
  • Escherichia coli Infections / drug therapy*
  • Escherichia coli Infections / epidemiology
  • Escherichia coli Infections / microbiology
  • Escherichia coli Proteins / drug effects
  • Escherichia coli Proteins / genetics
  • Fosfomycin / therapeutic use
  • Genotype
  • Humans
  • Klebsiella Infections / drug therapy
  • Klebsiella Infections / epidemiology
  • Klebsiella Infections / microbiology
  • Klebsiella pneumoniae / isolation & purification*
  • Methyltransferases / drug effects
  • Methyltransferases / genetics
  • RNA, Ribosomal, 16S / drug effects
  • RNA, Ribosomal, 16S / genetics
  • Trimethoprim, Sulfamethoxazole Drug Combination / therapeutic use*
  • Urinary Tract Infections / drug therapy
  • Urinary Tract Infections / epidemiology
  • Urinary Tract Infections / microbiology*
  • beta-Lactamases / drug effects
  • beta-Lactamases / genetics

Substances

  • Anti-Bacterial Agents
  • Escherichia coli Proteins
  • RNA, Ribosomal, 16S
  • Fosfomycin
  • Amoxicillin-Potassium Clavulanate Combination
  • Trimethoprim, Sulfamethoxazole Drug Combination
  • Methyltransferases
  • RmtB protein, E coli
  • beta-Lactamases
  • beta-lactamase CTX-M, E coli