The evolving epidemiology of antimicrobial resistance of ESKAPE pathogens isolated in the intensive care unit of a Greek university hospital

Background: The ESKAPE group (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter) is a major cause of life-threatening infections in Intensive Care Unit (ICU) critically ill patients accounting for significant morbidity and mortality. Management of infections by ESKAPE pathogens is complicated due to the remarkable rise in the rates of multidrug resistance (MDR) to most antimicrobial agents. This study investigated the trends of prevalence and antimicrobial resistance profiles of the ESKAPE pathogens isolated from clinical specimens of adult ICU patients. Methods: All ESKAPE isolates collected from clinical specimens of ICU patients during the years 2013-2022 were processed according to routine methods. Identification of the bacterial isolates was performed by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry and antimicrobial susceptibility testing by Vitek 2 system. Results: During the ten-year period, a total of 6,132 ESKAPE strains were isolated from 5,338 samples of 1,792 ICU patients. A. baumannii was the most prevalent microorganism, followed by P. aeruginosa, and K. pneumoniae. High resistance to carbapenems was detected for A. baumannii (96.7 %) and K. pneumoniae (57.4 %). Methicillinresistant were 39.1 % of S. aureus and vancomycin-resistant 38.7 % of the E. faecium isolates. MDR were characterized 39% of K. pneumoniae and 13.1 % of P. aeruginosa strains, while 19.7% of A. baumannii were pandrug resistant. Conclusions: An increased antimicrobial resistance among ESKAPE bacteria was found in our ICU setting. Enhanced antimicrobial surveillance, strict implementation of stewardship programmes and infection control practices are crucial to reduce AMR and develop management strategies to optimize outcomes.