Molecular Detection of Virulence Factors and Antibiotic Resistance among Enterococcus Species Isolates from Kurdistan Region of Iraq

Enterococcus spp., a part of the human normal flora, can acquire resistance to many antimicrobials. The existence of virulence determinants among the clinical isolates has led to the emergence of enterococci as potential pathogens in hospital settings. The study was performed to determine Enterococcus spp., the antibiogram, identify several virulence factors encoding genes, find the most prevalent genes from different sources, and determine the relationship of virulence factors with vancomycin resistance in both E. faecalis and E. faecium isolated from different clinical samples. Clinical isolates of enterococci were identified at the species level and then subjected to antibiotic susceptibility testing. The presence of seven virulence factors was investigated using the PCR technique. Various Enterococcal spp. have been identified among 116 clinical isolates; the two major species were E. faecalis (66.4%) and E. faecium (22.4%), and to a lesser extent, other Enterococcal spp. (11.2%). All the isolates were 100% resistant to tetracycline, and E. faecium isolates were significantly (P = 0.05) more resistant to ampicillin, trimethoprim-sulfamethoxazole, ciprofloxacin, penicillin, meropenem, nitrofurantoin, and fosfomycin. All the virulence factor genes (gelE. asa1, hyl, esp, cylA, ace, and efaA) were detected in E. faecalis and E. faecium isolates. Hyl and cylA rates were significantly higher among E. faecium isolates, while ace gene was significantly higher among E. faecalis isolates. All E. faecalis isolates possess one or more VFs, while one E. faecium isolate is free of VFs. Only two E. faecium isolates possessed all the VFs. There wasn't an evident link between the VFs and clinical samples. In conclusion, Enterococcus spp. has an elevated frequency and heterogeneity of virulence genes. The high resistance rate and virulence factor results emphasize the importance of E. faecalis and E. faecium isolates in causing infections in Kurdistan region. Larger-scale species identification and genotypic studies are needed in the region.