Characterization of Antimicrobial Resistance Mechanism(s) in Multi-Drug Resistant Enterococcus Clinical Isolates

Abstract

This study was concerned with screening clinical enterococcal bacterial isolates, from patients suffering from signs and symptoms of urinary tract infections (UTIs), bacteremia, and types of wounds for resistance against different antimicrobial agents commonly used in the treatment of such infections. The aim was to determine the prevalence of resistance among enterococcal pathogens to different antimicrobials and to detect the prevalence of multi-drug resistant (MDR) Enterococci isolates. The study also focused on the detection of efflux pump-mediated antimicrobial resistance and detecting the most common genes responsible for expression of efflux pumps, as this type of resistance can spread easily and rapidly among the microbial population. In the present study, a total of 149 clinical enterococcal bacterial isolates were obtained from the Microbiology laboratories of four hospitals in Cairo and Giza cities. The collected enterococcal species include E. faecalis (n=82), E. faecium (n=47), E. durans (n=11), E. avium (n=8), and E. casseliflavus (n=1). The susceptibilities of the recovered isolates to antimicrobial agents belonging to sixteen classes of antimicrobials commonly used to treat UTIs, bacteremia, and wounds were tested. The antimicrobial sensitivity of the collected enterococcal isolates showed that the highest levels of resistance were observed to ceftriaxone (65.8%); ampicillin (60.4%); and penicillin (51.6%). On