Virulence Genes and Antibiotic Susceptibility of Enterococcus spp. in Bandar Abbas City, Iran

In recent years, Enterococcus species have emerged as a leading cause of nosocomial infections worldwide. The aim of this study was to determine the virulence biomarkers and antibiotic resistance profiles of Enterococcus spp. collected from a main tertiary teaching hospital in Bandar Abbas, Iran.

A total of 71 Enterococcus were isolated from clinical specimens of patients in different wards of a hospital. Enterococcus spp. were verified by detecting ddl gene using PCR-based method. Virulence-encoding genes including gelE and cylA were detected using PCR. Antibiotic resistance was assessed using the disk diffusion assay, and vancomycin resistance was identified using the E-test method.

Among Enterococcus isolates, 50 and 21 isolates were identified as E. faecalis and E. faecium, respectively. Most of the Enterococcus species were isolated from urine, followed by wound samples. The most prevalent virulence genes among E. faecalis isolates were cylA (60%) and gelE (30%); also, 19 and 14% of E. faecium isolates were positive for cylA and gelE genes, respectively. Many isolates of E. faecalis (84%) and E. faecium (76%) were resistant to one or more antibiotics and showed high resistance to gentamicin and ciprofloxacin.

This study revealed a high prevalence of ciprofloxacin and gentamicin resistance and a high frequency of virulence genes among E. faecalis isolates. Due to the high prevalence of MDR Enterococcus strains, control measures are necessary to prevent the emergence and transmission of these strains in different hospital wards.