Detection of virulence factors of Enterococcus faecalis isolated from the urinary system and evaluation of antibiotic resistance

Aims: Enterococci, which are among the leading causes of nosocomial infections, are opportunistic pathogens and cause urinary tract infections most frequently. The frequency of isolation increases especially in patients with urinary system anomalies or urological interventions. Although various virulence factors play a role in the pathogenesis of infections caused by enterococci, cytolysin, hemolysin and enterococcal surface protein (ESP) are among the frequently investigated virulence factors. In this study; It was aimed to investigate the relationship between the presence of virulence factors and antibiotic resistance in Enteroccus faecalis (E. faecalis) strains isolated from urine samples, as well as the effect of urinary catheter use on these factors. Methods: 100 strains isolated from urine samples sent to İstanbul University İstanbul Faculty of Medicine Medical Microbiology Laboratory and identified as E. faecalis with the VITEK 2 (biomerioux-France) GP identification kit were included in the study. Hemolysin and gelatinase, virulence factors, were determined phenotypically. The presence of the ESP gene was investigated by PCR using ESP11 and ESP12 primers. Antibiotic sensitivities were studied by disk diffusion and gradient strip methods, and the results were evaluated in accordance with CLSI and EUCAST recommendations. Results: Antibiotic resistance rates were found to be 2%, 31%, 1%, 22%, 37% for ampicillin, norfloxacin, nitrofurantoin, high-level gentamicin (HLG) and high-level streptomycin (HLS), respectively, while no strains resistant to vancomycin, linezolid and tigecycline were detected. When evaluated in terms of virulence factors; It was determined that 82% of the strains produced gelatinase, 67% produced ESP, and 35% produced hemolysin. No virulence factor was detected in eight strains. Conclusion: In our study, no significant relationship was found between the presence of virulence factors and antibiotic resistance and catheter application. However, since the most detected gelatinase and ESP are virulence factors that have the ability to colonize and form biofilms on abiotic surfaces, it is thought that minimizing catheterization practices may contribute to the prevention of UTIs that may develop with enterococci.