Using Electric Cell-Substrate Impedance Sensing (ECIS) as a novel method to evaluate bacterial urinary tract infections

Abstract

Abstract Urinary tractinfections (UTIs) are commonly acquired bacterial infections that cause significant morbidity, worsened by the rise of antimicrobial resistance among uropathogenic bacteria. Understanding the dynamics of bacterial UTIs is essential to the proper use of antimicrobial therapies in patient treatment. In this study, Electric Cell-Substrate Impedance Sensing (ECIS) technology was used to monitor bacterial-mediated cytotoxicity in-vitro enabling evaluation of antibiotics. Using the ECIS system, real-time changes of barrier function were recorded for human bladder epithelial cells infected with either antibiotic sensitive or resistant bacteria. This study employed four common uropathogens: Pseudomonas aeruginosa, Escherichia coli, Enterococcus species, and Klebsiella pneumoniae. The effect of different antimicrobials, antibiotic titers, and organism concentrations were evaluated. The addition of an antibiotic helped confirm and differentiate sensitive and resistant bacterial strains. Antibiotic concentrations at sensitive and resistant breakpoints were not as effective at high organism concentrations but were completely effective at lower more clinically relevant bacterial loads. The data showed bacterial strains resistant to co-cultured antibiotic took longer on average to degrade the cell monolayer than sensitive strains. Overall, these results indicate that antibiotic resistance is often associated with a fitness cost. Our findings support the use of ECIS to augment routine susceptibility data allowing the direct phenotypic measurement of bacterial virulence and the effects of antibiotic treatment on these strains.