Comparison of clinical categories for Escherichia coli harboring specific qnr and chromosomal-mediated fluoroquinolone resistance determinants according to CLSI and EUCAST

Jesús Machuca; Alejandra Briales; Paula Díaz-de-Alba; Luis Martínez-Martínez; José-Manuel Rodríguez-Martínez; Álvaro Pascual

doi:10.1016/j.eimc.2015.01.019

Comparison of clinical categories for Escherichia coli harboring specific qnr and chromosomal-mediated fluoroquinolone resistance determinants according to CLSI and EUCAST

Enferm Infecc Microbiol Clin. 2016 Mar;34(3):188-90. doi: 10.1016/j.eimc.2015.01.019. Epub 2015 Mar 12.

Authors

Jesús Machuca¹, Alejandra Briales², Paula Díaz-de-Alba³, Luis Martínez-Martínez⁴, José-Manuel Rodríguez-Martínez⁵, Álvaro Pascual⁶

Affiliations

¹ Infectious Diseases and Clinical Microbiology Unit, University Hospital Virgen Macarena, Seville, Spain.
² Department of Microbiology, University of Seville, Seville, Spain; Spanish Network for the Research in Infectious Diseases (REIPI RD12/0015), Instituto de Salud Carlos III, Madrid, Spain.
³ Department of Microbiology, University of Seville, Seville, Spain.
⁴ Spanish Network for the Research in Infectious Diseases (REIPI RD12/0015), Instituto de Salud Carlos III, Madrid, Spain; University Hospital Marques de Valdecilla and Valdecilla Biomedical Research Institute (IDIVAL), Santander, Spain; Department of Molecular Biology, University of Cantabria, Santander, Spain.
⁵ Department of Microbiology, University of Seville, Seville, Spain; Spanish Network for the Research in Infectious Diseases (REIPI RD12/0015), Instituto de Salud Carlos III, Madrid, Spain. Electronic address: jmrodriguez@us.es.
⁶ Infectious Diseases and Clinical Microbiology Unit, University Hospital Virgen Macarena, Seville, Spain; Department of Microbiology, University of Seville, Seville, Spain; Spanish Network for the Research in Infectious Diseases (REIPI RD12/0015), Instituto de Salud Carlos III, Madrid, Spain.

PMID: 25772329
DOI: 10.1016/j.eimc.2015.01.019

Abstract

EUCAST breakpoints are more restrictive than those defined by CLSI. This study highlights the discrepancies between CLSI and EUCAST in a well characterized isogenic Escherichia coli collection and their correlations with specific quinolone resistance mechanisms. The greatest number of discrepancies was observed in strains containing 2-4 resistance mechanisms (MIC values on the borderline of clinical resistance). Bearing in mind that quinolones are concentration dependent antimicrobial agents, small changes in MIC may have relevant consequences for treatment outcomes.

Keywords: CLSI; EUCAST; Quinolonas; Quinolone; Resistance; Resistencia; qnr.

Publication types

Comparative Study
Research Support, Non-U.S. Gov't

MeSH terms

Anti-Bacterial Agents / pharmacology*
Drug Resistance, Bacterial / genetics*
Escherichia coli / drug effects
Escherichia coli / genetics*
Fluoroquinolones / pharmacology*
Humans
Microbial Sensitivity Tests

Substances

Anti-Bacterial Agents
Fluoroquinolones