Disarming Multidrug-Resistant Pathogens: Sodium Dodecyl Sulfate-Induced Plasmid Curing for the Reversal of Resistance and Virulence in Escherichia coli.

INTRODUCTION

The global escalation of multidrug-resistant (MDR) Escherichia coli poses a serious clinical challenge, largely driven by plasmid-mediated dissemination of antimicrobial resistance and virulence determinants. This study is aimed at evaluating the effectiveness of sodium dodecyl sulfate (SDS)-induced plasmid curing in reversing antimicrobial resistance and virulence phenotypes in clinical MDR E. coli isolates.

METHODS

A total of 485 clinical specimens were collected from hospitalized patients, yielding 190 E. coli isolates. All E. coli isolates (n = 190) were subjected to antimicrobial susceptibility testing and virulence phenotyping; of these, 63 were identified as MDR and subjected to plasmid profiling. A subset of 50 highly resistant isolates, defined as those resistant to ≥ 5 antimicrobial agents, was subsequently selected for SDS-mediated curing, followed by postcuring molecular and phenotypic reassessment.

RESULTS

E. coli was isolated from 39.2% of specimens, with 33.2% classified as MDR. SDS curing achieved 84.0% plasmid elimination, resulting in marked reductions in resistance to β-lactams and fluoroquinolones (≈45%-55%) and significant attenuation of virulence traits, including hemolysin production (53.3%) and motility (62.8%). All paired pre-/postcuring comparisons reached statistical significance (McNemar's test, p < 0.001 for the principal β-lactam, fluoroquinolone, and virulence outcomes). A strong molecular-phenotypic concordance (r S = 0.83) was observed.

CONCLUSIONS

SDS-induced plasmid curing effectively reverses resistance and virulence in clinical MDR E. coli, underscoring the central role of plasmids in shaping pathogenicity and supporting plasmid curing as an experimental laboratory tool rather than a clinically applicable intervention for dissecting plasmid-borne resistance and virulence determinants and informing future antimicrobial stewardship-aligned strategies.