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Salmonella spp. is the most frequently isolated foodborne pathogens causing human and animal diseases. The aim of this study was to investigate antimicrobial susceptibility profiles and the molecular typing of 200 Salmonella Enteritidis strains isolated from the patients' stools between 2016 and 2019 in Turkey. The isolates were examined for antibiotic susceptibility patterns (21 antimicrobial agents) by Kirby-Bauer disc diffusion method or molecular typing by Pulsed-field gel electrophoresis (PFGE) and plasmid profiling. Although all isolates were susceptible to four antibiotics (suphamethoxazole/trimethoprim, chloramphenicol, streptomycin and trimethoprim), all were resistant to 15 different antibiotics. In the PFGE study performed with XbaI enzyme, all isolates were found to be related to each other according to similarity rates of 85% and above. There were two major clones, clone A and B. Clone A was divided into 6 pulsotypes (A1-A2-A3-A4-A5-A6) and clone B was divided into 3 pulsotypes (B1-B2-B3). Clone A had 87% similarity and Clone B had 90% similarity. The clustering rate was 86% (172/200). All isolates harboured 1-4 plasmid ranging in size from 2.5 to 57 kb and showed 6 plasmid profiles (P1-P6). All isolates carried the 57 kb plasmid individually or in combination with other plasmids. Most of the isolates 136 (68%) had P2 profile. Our findings indicate that the majority of all isolates were clonally related and had cross contamination problems. In this study, the importance of molecular typing methods in order to take more effective protection and control measures against Salmonella has been demonstrated and proposed to use such methods. [ABSTRACT FROM AUTHOR]

Background/aim: The purpose of the study was to evaluate the performance of the VITEK mass spectrometry (MS) (bioMérieux, France) system for the identification of Klebsiella spp. isolated from different sources. Moreover, while assessing the ability of the VITEK 2 automated expert system (AES) to recognize antimicrobial resistance patterns, the researchers have extended the study to compare VITEK 2 with the routine antimicrobial susceptibility testing method. Materials and methods: This study tested 51 Klebsiella spp. isolates that were isolated from environmental examples and clinical examples. Results of conventional methods and the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS were compared. Then, any differing results were compared against a reference 16S rRNA gene sequence, and when indicated, a recA sequencing analysis was done. Results: VITEK MS correctly identified 100% of the Klebsiella spp. isolates. There were two K. oxytoca isolates incorrectly identified to the species level with conventional methods according to the 16S rRNA gene sequencing analysis. In addition, a VITEK 2 AST-N261 card was used for the detection of extended spectrum beta-lactamases (ESBL). Using the VITEK 2 AES, ESBL positivity was found at the rate of 16.3% whereas this rate was 4.08% using the disk diffusion method. Conclusion: MALDI-TOF MS is a rapid and accurate method for the identification of Klebsiella spp. Moreover, the bioMérieux AES provides a useful laboratory tool for the interpretation of susceptibility results. [ABSTRACT FROM AUTHOR]