Abstract
Background and Aims:
To enhance antimicrobial and infection control strategies, it is crucial for researchers to analyze shifts in bacterial susceptibility patterns contributing to healthcare-associated infections (HAIs). This study aims to evaluate the susceptibility patterns of Enterococcus species isolated from patients at a tertiary care hospital in Saudi Arabia over a 7-year period, with a particular focus on linezolid.

Methods:
We conducted a retrospective analysis of antimicrobial susceptibility trends among Enterococcus species isolated from various clinical samples, including blood, urine, wound swabs, and other body fluids, collected between 2015 and 2021. The study utilized surveillance data from King Khalid Hospital in Al Majmaah, Saudi Arabia.

Results:
A total of 514 Enterococcus species isolates were obtained during the study period from various clinical specimens, including blood, urine, and wound swabs with 466 (90.66%) demonstrating susceptibility and 48 (9.33%) showing resistance to linezolid. There were no documented cases of mixed infections (involving more than one organism) in these samples. Each isolate was treated as a unique infection episode, and the analysis focused solely on Enterococcus species. No multiple isolates of Enterococcus species were found in the same sample or from the same patient during the study period. Each patient contributed only one isolate for analysis, ensuring no duplication in the data.

Conclusions:
Linezolid has demonstrated efficacy against Enterococcus species, exhibiting favorable clinical outcomes and a low resistance rate, thus representing a promising and cost-effective therapeutic option for treating Enterococcus-associated infections.

Key words: Enterococci, VRE, Linezolid, Antimicrobial Resistance, Healthcare Associated Infections