Antimicrobial Resistance, Virulence Factors, Diversity, and Genetic Clonality of Enterococcus Species from Clinical Samples
Department of Microbiology, Tehran University, Iran
*Corresponding Author: Arezoo Asadi, Department of Microbiology, Tehran University, Iran.
Received: February 12, 2021 ; Published: June 24, 2021
Over the past decade, the emergence of antibiotic-resistant enterococci has posed critical challenges to the treatment of nosocomial infections around the world, and VRE infections have been associated with mortality and morbidity worldwide, especially in immunocompromised individuals. A total of 285 Enterococcus isolates were collected from patients referring to three major hospitals in Tehran from July to December 2012, and species were identified using biochemical tests and PCR. PCR assay and antibiotic susceptibility testing were performed to detect Enterococcus species, virulence factors, and resistance genes as well as to evaluate drug resistant isolates, respectively. The clonality of the isolates was also determined by PFGE. The isolates were found to consist of E. faecalis (65%) and E. faecium (31%) species. According to the results, 39 and 53% of E. faecalis and E. faecium isolates were resistant to the most commonly used antimicrobial agents, respectively. Also, acm (23, 64%) and hyl (6, 86%) were the most prevalent genes in E. faecalis isolates, while the most prevalent virulence genes in E. faecium isolates were cyt (7, 100%), gel (30, 97%), and asa (29, 97%). PFGE revealed a high heterogeneity among 50 VRE isolates. The emergence of multidrug-resistant and heterogeneous populations of enterococci is considered as a serious threat of global concern.
Keywords: Enterococcus; Resistance; Antimicrobials; PFGE
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