Comparative Analysis of Prevalence and Antibiotic Resistance in Vancomycin-Resistant Enterococcus from Clinical Samples – Demographics and Phenotypes

Folasade Muibat Adeyemi,Odunola Oluwaseun Oluwajide,Nana-Aishat Yusuf,Ajibade Kwashie Ako-Nai,Rashidat Ronke Adeboye

doi:10.34172/ajcmi.2021.11

Abstract

Background: Of all enterococci species, the most renowned clinically as multidrug-resistant pathogens are Enterococcus faecium and Enterococcus faecalis. Vancomycin-resistant Enterococcus (VRE) species are the principal cause of opportunistic hospital-acquired infections, due to numerous resistance mechanisms. Methods: In this study, the prevalence and antibiotic resistance profiles of VRE according to clinical sources from three selected hospitals in Southwest-Nigeria were investigated. Altogether, 431 samples (urine, rectal, and wound swabs - caesarian section (CS), automobile accidents, and other skin lesions and abrasions) were collected from three selected hospitals in Osun State, Nigeria. Established techniques were employed for the recovery of enterococci and screening for VRE while antibiotic susceptibility tests were carried out by disc diffusion technique. Results: Altogether, 208 (48.3%) enterococci strains were recovered from which 85 (40.9%) were VRE. E. faecium predominated at 71.8% (61/85) and E. faecalis at 28.2% (24/85) as determined by phenotypic characterization. VRE isolates exhibited 100%, 97.6%, and 92.9% resistance to ampicillin, clindamycin, and quinupristin-dalfopristin (Q/D) respectively. The least resistance in-vitro was to tigecycline (27.1%). None of the antibiotics exhibited 100% activity against all the isolates. vanA resistant phenotype was prevalent at 65.9%. E. faecium from all study locations displayed higher levels of resistance than E. faecalis. Multiple antibiotic resistance (MAR) indices in all VRE isolates were ≥0.2, all being multidrug-resistant. Conclusions: The high prevalence rate along with the high level of multidrug resistance observed in the present study is worrisome and poses a continuous threat in the therapy of illnesses triggered by VRE as vancomycin was perceived as a drug of choice to curb enterococcal infections.

Highlights

Of all enterococci species, the most renowned clinically as multidrug-resistant pathogens are Enterococcus faecium and Enterococcus faecalis
Enterococcus faecium and Enterococcus faecalis reportedly being within the top three most significant nosocomial pathogens globally [2], are progressively more recognized and have emerged as clinically important multidrug-resistant infectious pathogens. They are implicated in many infections including bacteremia, endocarditis, urinary tract, intra-abdominal, pelvic, surgical site, and diabetic foot ulcer [3,4]. This involvement could be due to their intrinsic resistance to different antibiotics, development of antibiotic resistance [2] with ability to adapt quickly in the health-care setting, and extreme genetic variations coupled with the incidence of a variety of virulence determinants [4], making enterococcal infections serious and life-threatening
This is of public health importance as infections caused by Vancomycin-resistant Enterococcus (VRE) are challenging to manage in the clinical environment, and the strains are capable of spreading between hospitals and districts [7]

Summary

Introduction

The most renowned clinically as multidrug-resistant pathogens are Enterococcus faecium and Enterococcus faecalis. Enterococcus faecium and Enterococcus faecalis reportedly being within the top three most significant nosocomial pathogens globally [2], are progressively more recognized and have emerged as clinically important multidrug-resistant infectious pathogens They are implicated in many infections including bacteremia, endocarditis, urinary tract, intra-abdominal, pelvic, surgical site, and diabetic foot ulcer [3,4]. Multiple resistance mechanisms in VRE have led to limitations in available treatment options as increased vancomycin resistance in enterococci restricts the choice of vancomycin as a treatment for enterococcal infections [6] This is of public health importance as infections caused by VRE are challenging to manage in the clinical environment, and the strains are capable of spreading between hospitals and districts [7]

Methods

Results

Conclusion