Prevalence of Multidrug-Resistant Enterococcus faecalis in Hospital-Acquired Surgical Wound Infections and Bacteremia: Concomitant Analysis of Antimicrobial Resistance Genes

Abstract

Background The study aimed to assess the prevalence of Enterococcus faecalis infections among patients with hospital-acquired surgical wound sepsis and bacteremia in surgical wards and identify the antimicrobial susceptibility in these pathogens. Genetic role of erythromycin, vancomycin, and cephalosporin resistance in these pathogens was also examined. Methods Two hundred samples were collected from surgical wound infections and 100 blood cultures from patients with suggested bacteremia to identify E faecalis by phenotypic and genotypic methods. Antimicrobial susceptibility to 12 antimicrobial agents was tested. The presence of resistance genes was examined by polymerase chain reaction (PCR) assay. Results E faecalis was isolated with a frequency of 24/200 (12%) from surgical wound samples and 2/100 (2%) from blood cultures. All isolates were completely resistant to cefepime, ampicillin, and tetracycline, 96% of isolates were resistant to erythromycin, 53.8% to vancomycin, and 23.1% to linezolid. Multidrug resistance (MDR) was found in 100% of isolates. ere(B) and erm(B) genes were present in 20/25 (80%) and 17/25 (68%) of erythromycin-resistant isolates, respectively, 15 (60%) isolates carry both ere(B) and erm(B) genes. Van A gene was detected in 71.4% of vancomycin-resistant isolates. All isolates were negative for mef(A/E), blaSHV, and blaTEM genes. Conclusion MDR in all isolates (100%) and high-level resistance to gentamicin, erythromycin, and vancomycin were reported in E Faecalis isolates. In the studied isolates, erythromycin resistance mainly related to the presence of ere(B) and erm(B) genes and vancomycin resistance was mainly related to the presence of vanA gene.