[Plasmids of Enterococcus faecium strains isolated from patients of different wards of General Hospital in Gdańsk].

Introduction: Mobil genetic elements are pivotal in the dissemination and persistence of antimicrobial resistance in enterococci. This study investigated the presence of plasmids amongst E. faecium as well as other species of this bacteria.

Methods: Bacterial strains were identified as described previously. Plasmid DNA isolation and digestion with restriction endonucleases were described. The fragments ofplasmid DNA were separated by electrophoresis.

Results: Most of the isolates had multiple plasmids, particularly the E. faecium strains. The same plasmid were observed in the same species of enterococci as well as in the other. Plasmid patterns suggested that some of the E. faecium strains were shared between wards.

Conclusions: The occurrence of several unrelated strains with the same plasmids may indicate horizontal spread of genetic elements.