Phenotypic and genotypic characterization of vancomycin-resistant enterococcus isolates from clinical specimens:  A cross-sectional study.

Monalisa  Panigrahi; Bimoch Projna  Paty; Banojini  Parida

doi:10.51168/sjhrafrica.v6i9.2147

Authors

Monalisa Panigrahi Assistant Professor, Department of Microbiology, SJMCH, Puri, Odisha, India
Bimoch Projna Paty Professor and HOD, Department of Microbiology, SJMCH,Puri, Odisha, India
Banojini Parida Ex. HOD, Microbiology Department, MKCG,MCH, Berhampur, Odisha, India

DOI:

https://doi.org/10.51168/sjhrafrica.v6i9.2147

Keywords:

Vancomycin-resistant Enterococcus, vanA gene, Antimicrobial resistance, Hospital-acquired infection, monalisa et al

Abstract

Background
Enterococci are Gram-positive bacteria that form part of the human gut flora but have emerged as significant nosocomial pathogens. The increasing prevalence of vancomycin-resistant enterococci (VRE) poses major therapeutic and infection-control challenges. This study aimed to determine the prevalence of vancomycin resistance among clinical Enterococcus isolates and to characterize the associated phenotypic and genotypic resistance profiles.

Methodology
A cross-sectional study was conducted in the Department of Microbiology, MKCG Medical College and Hospital, Berhampur, Odisha, from October 2017 to September 2019. One hundred non-duplicate Enterococcus isolates recovered from urine, blood, pus/wound swabs, and sterile body fluids were identified based on standard biochemical tests. Antimicrobial susceptibility was performed using the Kirby–Bauer disc diffusion method as per CLSI 2019 guidelines. Vancomycin resistance was screened on VRE agar and confirmed by MIC via E-test. Genotypic detection of vanA and vanB resistance genes was performed using multiplex real-time PCR. Basic demographic variables, including age and sex, were recorded.

Results
Of the 100 isolates, 64% were E. faecalis, 31% were E. faecium, and 5% were E. durans. The mean age of affected patients was 38.6 years, with a female predominance (56%). The prevalence of VRE was 23%, with E. faecium accounting for most resistant isolates (69.6%). VRE isolates demonstrated high resistance to ampicillin (100%), ciprofloxacin (95.7%), high-level gentamicin (82.6%), and teicoplanin (78.3%), while all isolates remained susceptible to linezolid. All VRE isolates carried the vanA gene; vanB was not detected. Heteroresistance was identified in five isolates.

Conclusion
vanA-mediated VRE is prevalent in hospital settings and associated with multidrug resistance.

Recommendation

Routine surveillance, molecular detection, and strengthened antimicrobial stewardship are essential to limit VRE dissemination.

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