Virulence genes in Enterococcus spp. strains, isolated from blood cultures of patients hematological malignancies in Russia

Khrulnova S.A., Fedorova A.V., Klyasova G.A.

Enterococci are among the leading causative agents of sepsis in patients with hematological malignancies. These microorganisms, along with different parameters of susceptibility, have different virulence genes that may be important in the infectious process. The aim of the study. To study the presence of virulence genes esp, asa1, cylA, hyl and gelE among Enterococcus spp. isolated from blood cultures in patients with hematological malignancies.
Results. Enterococcus spp. were isolated from blood in 12 hospitals in Russia. A total of 363 Enterococcus spp. isolates (281 (77.4%) E. faecium, 74 (20.4%) E. faecalis, 8 (2.2%) others (5 E. gallinarum, 2 E. durans and 1 E. hirae)) were examined. Resistance to vancomycin was detected in 37 (13.2%) E. faecium (VREfm) and one (1.4%) E. faecalis (VREfs). VREfm carried genes of vanA (78.4%, 29) and vanB (21.6%, 8). Virulence genes were detected in 334 (92%) strains of Enterococcus spp. Tested genes were not found in 29 (8%) strains: 23 (8.2%) E. faecium, 3 (4.1%) E. faecalis, 3 (37.5%) others (1 E. gallinarum, 1 E. durans, and 1 E. hirae). Genes esp and hyl prevailed among E. faecium (75.8% and 65.5%, respectively), genes asa1 and gelE – E. faecalis (62.2% and
68.9%, respectively).
Conclusion. E. faecium strains were dominated among Enterococcus spp. isolated from blood cultures. The most strains had virulence genes. It has been shown that different virulence genes were predominant in E. faecium and E. faecalis