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High-throughput Assay to Phenotype Salmonella enterica Typhimurium Association, Invasion, and Replication in Macrophages
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[Salmonella enterica with nonclassical quinolone resistance phenotype in pediatric patients]

Ma José González-Abad1, Mercedes Alonso-Sanz

  • 1Mª José González-Abad, Hospital Infantil Universitario Niño Jesús, Avda. Menéndez Pelayo, 65, 28009 Madrid, Spain. mjglezabad@yahoo.es.

Revista Espanola De Quimioterapia : Publicacion Oficial De La Sociedad Espanola De Quimioterapia
|February 19, 2015
PubMed
Abstract

Insights

The study found a low incidence of nonclassical quinolone resistance in pediatric Salmonella isolates. Identifying these strains is challenging, but their potential for spread warrants monitoring for changes in resistance trends.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Context:

  • Fluoroquinolone resistance in Salmonella spp. can lead to treatment failures.
  • Understanding quinolone resistance in pediatric Salmonella is limited.
  • Nonclassical quinolone resistance phenotypes pose diagnostic challenges.

Purpose:

  • To assess the incidence of nonclassical quinolone resistance phenotypes in pediatric Salmonella isolates.
  • To investigate the prevalence of plasmid-mediated quinolone resistance genes (qnr) in these strains.

Summary:

  • A study of 268 Salmonella isolates from pediatric patients identified four with a nonclassical quinolone resistance phenotype.
  • Three of these four isolates carried plasmid-mediated qnr genes.
  • The overall incidence of this resistance phenotype was low in the studied population.

Impact:

  • Highlights the difficulty in identifying nonclassical quinolone resistance using conventional methods.
  • Emphasizes the importance of monitoring for horizontal gene spread of resistance.
  • Suggests periodic evaluation of resistance trends rather than routine MIC testing for all susceptible strains due to low incidence.

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