Concha-Valdez FG, Flores-Abuxapqui JJ, Puc-Franco MA, Heredia-Navarrete MR

Language: Spanish
References: 22
Page: 201-206
PDF size: 63.33 Kb.

ABSTRACT

Introduction. Plasmids contribute importantly to Salmonella virulence. Many Salmonella serotypes contain virulence plasmids (spv) that enhance their capacity for systemic infection in experimental animals (mice, cattle) after oral inoculation. The role of the virulence plasmid on the pathogenesis of salmonellosis or septicemia has been mainly studied in the murine model, while few studies have tried to establish the relationship between virulence plasmids and the presence of diarrhea in humans.
Materials y Methods. We studied 50 strains of Salmonella spp. isolated from children with diarrhea and 120 without diarrhea. We used the PCR method to amplify a 200 bp fragment of the spvB gene in order to investigate its presence in the samples.
Results. From the 50 strains isolated from children with diarrhea, in 16 (32%) the spvB gene was amplified, and 34 (68%) were negative. From the 120 strains isolated from children without diarrhea, in 20 (17%) the spvB gene was amplified and 100 (83%) were negative. A value of 4.09 for c² was determined (p = 0.043). Thus, from 170 strains studied, 36 (21%) were positive to the presence of the spvB gene, and 134 (79%) were negative.
Conclusions. We observed a significant association between the spvB gene presence and diarrhea in children.

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