1.Distribution of resistance genes and virulence genes in multidrug-resistant Salmonella typhimurium strains
Yufeng ZHANG ; He SONG ; Le YAN ; Pengfei XU ; Ruiqing LIU ; Tiantian TANG ; Xiaoyan WANG ; Huiling DENG ; Kairui LEI
Chinese Pediatric Emergency Medicine 2024;31(11):831-835
Objective:To study the distribution of drug resistance genes and virulence genes in multidrug-resistant Salmonella typhimurium strains.Methods:A total of 96 strains of Salmonella typhimurium were collected,and drug sensitivity tests were performed to evaluate the drug resistance and multidrug-resistance of Salmonella typhimurium.Multidrug-resistant Salmonella typhimurium strains were selected to conducted whole genome sequencing,and the distribution of drug resistance genes and virulence genes in the strain were analyzed.Results:Salmonella typhimurium strains had the highest resistance rates to ampicillin and ampicillin/sulbactam,with 89.58% and 76.04%,respectively.Followed by trimethoprim/sulfamethoxazole,ceftriaxone,and aztreonam,with 47.92%,38.54% and 33.33%,respectively,and low resistance rates to ciprofloxacin and levofloxacin,with 8.33% and 4.17%,respectively.Ninety-six strains were all sensitive to carbapenem antibiotics and piperacillin/tazobactam.Fifty-seven strains(59.38%)of Salmonella typhimurium showed multidrug-resistance.Resistance genes were detected in all 57 multidrug-resistant Salmonella typhimurium strains,with higher carrier rates of 98.25%,77.19%,and 59.65% for aac(6')-Iaa,aadA22,and blaTEM-1B,respectively.The multidrug-resistant Salmonella typhimurium strains had the highest carrier rates for invA,sipA,sseL,and sopB.Conclusion:Multidrug-resistant Salmonella typhimurium strains have a high incidence and a high carrier rate for multiple drug resistance genes and virulence genes.The monitoring and prevention of Salmonella typhimurium should be strengthened in the clinic in order to reduce the spreading epidemic of multidrug-resistant strains.