An insight into selection specificity of quinolone resistance determinants within Enterobacteriaceae family

Nivedita Dasgupta; Deepjyoti Paul; Debadatta Dhar Chanda; Birson Ingti; Dibyojyoti Bhattacharjee; Atanu Chakravarty; Amitabha Bhattacharjee

doi:10.1016/j.jgar.2017.03.010

An insight into selection specificity of quinolone resistance determinants within Enterobacteriaceae family

J Glob Antimicrob Resist. 2017 Sep:10:40-46. doi: 10.1016/j.jgar.2017.03.010. Epub 2017 Jun 12.

Authors

Nivedita Dasgupta¹, Deepjyoti Paul¹, Debadatta Dhar Chanda², Birson Ingti¹, Dibyojyoti Bhattacharjee³, Atanu Chakravarty², Amitabha Bhattacharjee⁴

Affiliations

¹ Department of Microbiology, Assam University, Silchar, Assam, India.
² Department of Microbiology, Silchar Medical College and Hospital, Silchar, Assam, India.
³ Department of Statistics, Assam University, Silchar, Assam, India.
⁴ Department of Microbiology, Assam University, Silchar, Assam, India. Electronic address: ab0404@gmail.com.

PMID: 28619611
DOI: 10.1016/j.jgar.2017.03.010

Abstract

Objectives: Quinolone antimicrobials are frequently misused due to self-medication and suboptimal dose administration, leading to the development of resistance as well as treatment failure. The present study aimed to characterise plasmid-mediated quinolone resistance (PMQR) determinants and their genetic selection in the presence of quinolone stress within members of the Enterobacteriaceae.

Methods: A total of 209 non-duplicate Enterobacteriaceae isolates were collected from hospital and community health centres over the period July 2013-June 2014. Molecular characterisation of phenotypically screened quinolone-resistant isolates was done by multiplex PCR. Plasmids bearing the qnr and aac(6')-Ib-cr genes were transformed into Escherichia coli DH5α and were selected on Muller-Hinton agar plates containing 0.25μg/mL and 0.5μg/mL ciprofloxacin, norfloxacin, ofloxacin, levofloxacin and moxifloxacin. Conjugation experiments were performed to determine whether the aac(6')-Ib-cr- and qnr-carrying plasmids were self-transferable.

Results: The transformation assay revealed that transformants carrying qnrA could be selected in media containing norfloxacin, ciprofloxacin and levofloxacin, whereas qnrB and aac(6')-Ib-cr were selected on media containing norfloxacin and ciprofloxacin. Transformed qnrD could be selected in media containing norfloxacin and ofloxacin, and qnrS was selected only in the presence of levofloxacin.

Conclusions: The presence of qnr genes has been associated with an increase in quinolone minimum inhibitory concentrations (MICs) and therefore leads to treatment failure when quinolones are used as selective therapeutic drugs. Since PMQR determinants have a high prevalence, effective measures should be taken and surveillance should be performed in order to avoid treatment failures using this group of antimicrobials.

Keywords: Antimicrobial use; Plasmid-mediated antimicrobial resistance; Quinolone resistance; Resistance gene.

MeSH terms

Anti-Bacterial Agents / pharmacology*
Bacterial Proteins / genetics*
Bacterial Typing Techniques / methods
Bacterial Typing Techniques / veterinary*
Biomarkers
Community Health Centers
Drug Resistance, Bacterial / genetics*
Enterobacteriaceae / drug effects*
Enterobacteriaceae / genetics*
Enterobacteriaceae / isolation & purification
Enterobacteriaceae Infections / microbiology
Escherichia coli / genetics
Escherichia coli Proteins / genetics
Gene Transfer, Horizontal
Genes, Bacterial / genetics
Hospitals
Humans
India
Microbial Sensitivity Tests
Molecular Epidemiology
Multiplex Polymerase Chain Reaction
Plasmids / genetics
Prevalence
Quinolones / pharmacology*
Quinolones / therapeutic use
R Factors / genetics*

Substances

Anti-Bacterial Agents
Bacterial Proteins
Biomarkers
Escherichia coli Proteins
Qnr protein, E coli
Quinolones