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[Investigation of plasmid-mediated quinolone resistance determinants in Enterobacteriaceae: a multicenter study]

Ahmet Yılmaz Coban1, Okan Kadir Nohut, Yeliz Tanrıverdi Çaycı

  • 1Ondokuz Mayıs University Faculty of Medicine, Department of Medical Microbiology, Samsun, Turkey. cobanay2003@yahoo.com.tr

Mikrobiyoloji Bulteni
|September 7, 2012
PubMed

Insights

This study identified plasmid-mediated quinolone resistance genes (qnr) in Turkish Enterobacteriaceae isolates, highlighting a growing threat to antibiotic effectiveness. Understanding qnr gene prevalence is crucial for infection control and combating antimicrobial resistance.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Genetics

Context:

  • Fluoroquinolones are broad-spectrum antibiotics crucial for treating bacterial infections.
  • Emerging plasmid-mediated quinolone resistance (PMQR) via qnr genes poses a significant challenge to antimicrobial therapy.
  • Understanding the prevalence and types of qnr genes is essential for effective infection control.

Purpose:

  • To investigate the presence and types of plasmid-mediated quinolone resistance determinants (qnrA, qnrB, qnrC, qnrS) in Enterobacteriaceae isolates from Turkey.
  • To confirm the identified qnr genes using gene sequencing.
  • To assess the association of qnr genes with reduced susceptibility to quinolone antibiotics.

Summary:

  • A total of 647 Enterobacteriaceae isolates were collected from four centers in Turkey.
  • Multiplex PCR detected qnrA, qnrB, qnrC, and qnrS genes, with subsequent gene sequencing identifying specific qnr alleles.
  • Specific qnr alleles (qnrA1, qnrB1, qnrB6, qnrB9, qnrB24, qnrB27, qnrS1, qnrB2) were identified in various Enterobacteriaceae species.
  • A small number of qnr-positive isolates exhibited resistance to nalidixic acid and ciprofloxacin.

Impact:

  • The findings reveal the presence of transferable quinolone resistance mechanisms in Turkey, potentially complicating treatment and infection control.
  • Dissemination of qnr genes can lead to increased minimum inhibitory concentrations and treatment failures.
  • This study underscores the need for continuous surveillance of PMQR to guide antimicrobial stewardship and prevent further resistance escalation.

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