Virulence Factors Profile of Staphylococcus Aureus Isolated from Different Clinical Sources. By

In this study, a number of 85 Staphylococcus aureus isolates were collected from various clinical sources including diabetic foot, burns, urine, wound, abcesses, boils, nasal discharge and vaginal smear from 135 inpatients at different Mansoura hospitals, Dakahlia governorate, Egypt. Isolates were phenotypically investigated for some virulence factors (biofilm, lipase, protease, staphylokinase (SAK), lecithinase, hemolysin and hemagglutination). It was found that biofilm was the highest detected virulence factor among isolates (82.3 %) and SAK was the lowest detected factor (41.15 %). Moreover, five staphylococci toxin encoding genes (hla, hlb, hlg, hld, and tsst-1) were detected by PCR. These genes were harboured by 30.5 %, 70.5 %, 81.1 %, 88.2 % and 64.7% of isolates respectively. Concerning the isolation source, diabetic foot isolates showed higher prevalence of biofilm (21.7 %), staphylokinase (12.94 %), lipase (20 %), protease (17.6 %), hemagglutination (18.8 %), tsst-1 (17.64 %), hlb (18.2 %), hlg (18.82 %) and hld (21.17%). While isolates from burns showed the highest hemolysin and lecithinase production. Moreover, urine isolates showed the highest prevalence of hla gene. In conclusion virulence profile pattern was used to evaluate the association between virulence factors and isolation source, but no significant correlation was revealed. The present study ensure the high variability in the distribution of virulence factors among isolates from different sources create a compelling arguments to reconsider the appropriateness of assessing virulence potential of S. aureus in order to control S. aureus infection. Moreover, diabetic foot isolates showed the highest prevalence of virulence determinants with mean virulence score (8.45) which increases the risk factor of death in diabetic foot patients.