The emergence of carbapenem-resistance and New Delhi   metallo-β-lactamase-1 (bla    NDM-1   ) among Salmonella spp. in Kerman, Iran

Sanaz Dehdashti; Parvin Mohseni; Reza Ghanbarpour; Sajad Aslani; Maryam-Sadat Moradiyan; Davood  Kalantar-Neyestanaki

doi:10.18502/ijm.v16i1.14868

Sanaz Dehdashti Student Research Committee, Kerman University of Medical Sciences, Kerman, Iran
Parvin Mohseni Department of Pathobiology, Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, Kerman, Iran
Reza Ghanbarpour Molecular Microbiology Research Group, Shahid Bahonar University of Kerman, Kerman, Iran
Sajad Aslani Department of Pharmaceutics, Faculty of Pharmacy, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Maryam-Sadat Moradiyan Student Research Committee, Kerman University of Medical Sciences, Kerman, Iran
Davood Kalantar-Neyestanaki Medical Mycology and Bacteriology Research Center, Kerman University of Medical Sciences, Kerman, Iran

DOI: https://doi.org/10.18502/ijm.v16i1.14868

Keywords: Salmonella; Beta-lactamase genes; Virulence factors; New Delhi metallo-beta-lactamase-1 (NDM-1)

Abstract

Background and Objectives: Salmonella species (spp) are the most prevalent zoonotic pathogens that cause outbreaks of gastroenteritis worldwide. Therefore evaluation of the profile of antibiotic resistance, virulence factors, and plasmid replicon types in these bacteria is necessary to control and prevent the spread of potentially pathogenic and drug-resistant strains.

Materials and Methods: This study was performed on 39 Salmonella spp. The antibacterial susceptibility of isolates to various antibiotic agents was determined using disk diffusion test. β-lactamases (bla) including ESBLs, AmpC, MBLs, and virulence genes were detected by PCR methods. Plasmid incompatibility groups among the isolates were identified using PCR-based replicon typing (PBRT).

Results: The most prevalent virulent gene was phoP/Q (84.6%). slyA, sopB, and stn were identified in 79.4% (n=31), 69.2% (n=27), and 2.5% (n=1) of the isolates, respectively. The antibiotic susceptibility testing showed that 30.7% of the isolates were ESBL-producing. bla TEM (41%; n=16) was the most frequent β-lactamase gene among the isolates followed by bla NDM-1 (15.4%; n=6), bla DHA (7.7%; n=3), and bla CTX-M (1.5%; n=1). Six different plasmid replicon types, including IncP (n=9; 23%), IncFIC (n=3; 7.70%), IncY (n=3; 7.70%), IncI1-Iγ (n=2; 5.12%), IncFIIAs (n=1; 2.56%), and IncN (n=1; 2.56%) were ob- served among the isolates.

Conclusion: Our study showed the emergence of carbapenem-resistant and bl NDM-1among Salmonella spp. for the first time in Kerman, Iran. Since Salmonella spp. plays an important role in the transmission of resistance genes in livestock and humans in the food chains, so more stringent control policies are recommended to prevent the circulation of drug-resistant and potentially pathogenic strains from animals to humans.