Abstract
Background: The aim of this study was to investigate the phenotypic features (adherence, biofilm formation, virulence, antibiotic susceptibility) and the genetic background of antibiotic resistance in nosocomial ESCAPE strains consecutively isolated from surgical wound infections in hospitalized patients.
Methods: 86 bacterial strains consecutively isolated from various wound infections were analysed by their antibiotic resistance (antibiotic susceptibility testing and PCR for certain antibiotic resistance genes), virulence, biofilm formation and cellular adherence.
Results: The bacterial isolates were identified as: Enterobacterales (n = 39) including Escherichia coli (n = 9), Klebsiella pneumoniae (n = 14) Proteus mirabilis (n = 7), followed by Staphylococcus aureus (n = 26) and Enterococcus faecalis (n = 20). Compared to other isolates, S. aureus strains exhibited the highest capacity to produce soluble virulence factors and to develop biofilms in vitro, with significant differences between methicillin resistant and methicillin susceptible isolates. Among enterobacterial isolates, K. pneumoniae strains expressed the highest capacity to develop biofilms. The assessment of bacterial adherence to HeLa cells revealed that all bacterial strains adhered to the cellular substrata, showing various adherence patterns. E. faecalis strains exhibited a low soluble virulence factors profile, a lower capacity to adhere to epithelial cells and to develop biofilms.
Conclusions: The present study could contribute to the understanding of the pathology of infected wounds, depending on the etio-logical agents, providing data with positive impact on the therapeutic management of surgical wounds infections.