Phenotypic and molecular characterization of β-lactamase and plasmid-mediated quinolone resistance genes in Klebsiella oxytoca isolated from slaughtered pigs in Thailand

Vet World Vol.15 February-2022 Article-10

Research Article

Veterinary World, 15(2): 309-315

https://doi.org/10.14202/vetworld.2022.309-315

Nattamol Phetburom¹, Parichart Boueroy¹, Peechanika Chopjitt¹, Rujirat Hatrongjit², Suphachai Nuanualsuwan³, and Anusak Kerdsin¹

1. Department of Community Health, Faculty of Public Health, Kasetsart University, Chalermphrakiat Sakon Nakhon Province Campus, Sakon Nakhon, Thailand.
2. Department of General Sciences, Faculty of Science and Engineering, Kasetsart University, Chalermphrakiat Sakon Nakhon Province Campus, Sakon Nakhon, Thailand.
3. Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand.

Background and Aim: Over recent years, antimicrobial-resistant Klebsiella species in humans, animals, food animals, food products, and agricultural environments have been the center of attention due to its role in the evolution of antimicrobial resistance. The emergence of resistance to fluoroquinolones and cephalosporins of third and higher generations in Klebsiella oxytoca has not received much attention in animal husbandry compared to that in Klebsiella pneumoniae. Reports on K. oxytoca are limited in the study area. Therefore, we investigated the antimicrobial susceptibility and resistance genes in K. oxytoca isolated from slaughtered pigs in Thailand.

Materials and Methods: Microbiological examination was conducted on 384 Klebsiella spp. isolates recovered from slaughtered pigs in ten provinces of Thailand. Seventy-two K. oxytoca isolates (18.75%) were examined for antimicrobial-resistant genes (β-lactamase [blaTEM, blaCTX-M, and blaSHV]) and fluoroquinolone-resistant genes (qnrA, qnrB, qnrC, qnrD, qnrS, oqxAB, aac(6')-Ib-cr, and qepA).

Results: The most common genotype was blaCTX-M (58/72, 80.55%), followed by blaTEM with blaCTX-M (7/72, 9.72%) and blaTEM (6/72, 8.33%). The most common blaCTX-M group was blaCTX-M-1 (19/58, 32.76%), followed by blaCTX-M-9 (1/58, 1.72%). Plasmid-mediated quinolone resistance genes were identified in 13 (18.05%) isolates: qnrS (16.70%) and qnrB (1.4%). All 13 isolates had qnrS transferable to an Escherichia coli recipient, whereas qnrB was not detected in any transconjugants. Either blaCTX-M or blaTEM harbored by one K. oxytoca strain was transferable to an E. coli recipient. Analysis of antimicrobial susceptibility revealed that more than 90% of the blaCTX-M-carrying K. oxytoca isolates were susceptible to chloramphenicol, trimethoprim, ceftazidime, cefepime, cefotaxime, amoxicillin-clavulanic acid, piperacillin–tazobactam, and fosfomycin. All K. oxytoca isolates (13) harboring qnr were susceptible to carbapenem and ceftriaxone; however, 43 (74.13%) of the K. oxytoca isolates harboring blaCTX-M exhibited extended-spectrum β-lactamase activity. Most of the K. oxytoca isolates from pigs were highly resistant to ampicillin, azithromycin, and gentamicin.

Conclusion: To prevent further transmission of Klebsiella spp. between food animals and humans, strict control of antibiotic use in clinical and livestock settings is necessary along with routine disinfection of the livestock environment and efforts to increase awareness of antimicrobial resistance transmission. Keywords: Klebsiella oxytoca, plasmid-mediated quinolone resistance, slaughtered pigs, Thailand, β-lactamase.

Keywords: Klebsiella oxytoca, plasmid-mediated quinolone resistance, slaughtered pigs, Thailand, β-lactamase.

How to cite this article: Phetburom N, Boueroy P, Chopjitt P, Hatrongjit R, Nuanualsuwan S, Kerdsin A (2022) Phenotypic and molecular characterization of β-lactamase and plasmid-mediated quinolone resistance genes in Klebsiella oxytoca isolated from slaughtered pigs in Thailand, Veterinary World, 15(2): 309-315.

Received: 04-10-2021 Accepted: 12-01-2022 Published online: 13-02-2022

Corresponding author: Parichart Boueroy E-mail: parichart.bou@ku.th

DOI: 10.14202/vetworld.2022.309-315

Copyright: Phetburom, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.