Comparison of Virulence Genes (int, inv, spv (vir)) in Salmonella typhimurium and infantis from Clinical Cases by Multiplex PCR

virulence genes in Salmonella are a combination of plasmid and chromosomal factors and a single genetic position would not be responsible for all biological manifestations in Salmonella. Considering the difference in the serotypes of Salmonella in terms of serious genes, the aim of this study was to compare the presence of plasmid and chromosomal virulence genes (int, inv, spv (vir)) Salmonella typhimurium and Infantis in clinical cases in children and adults by Multiplex PCR.

In this study, 676 stool specimens were collected from patients referring to Imam Khomeini and Milad hospitals and 60 isolates were identified as Salmonella. After serotyping, 30 isolates were recognized as Salmonella infants and 30 isolates as salmonella typhimurium. By using the Multiplex PCR technique, the prevalence of spvC, invA and Int genes was studied.

All investigated serotypes had invA and Int genes. 93.3% of typhimurium serotypes and 6/7% of infantis serotypes infants had SpvC gene. In 93/3% of typhimurium serotypes and 6/7% of infantis serotypes all three genes were present simultaneously.

virulence genes increase the pathogenicity of typhimurium and Infantis strains. Therefore, the genetic and molecular genetic isolation of these genes can help to identify the bacterial enzymes and to make effective drugs for the treatment of related diseases.