EN
Of 274 fecal coliforms isolated from two watercourses influencing the costal water quality of the Gdańsk and Puck bays, 265 were identified as Escherichia coli. The remained strains belonged to: Acinetobacter spp. (n=1), Enterobacter spp. (n=3), Klebsiella spp. (n=4), and Shigella spp. (n=1). The susceptibility of 222 E. coli was tested against 19 antimicrobial agents: aminoglycosides, carbapenems, cephalosporines, folate antagonists, fluoroquinolones, monobactam, penicillins, penicillins/β-lactamase inhibitors, and tetracycline. The highest number of isolates was resistant to penicillins (ampicillin 21% and piperacillin 14%), as well as to tetracycline (16%). Up to 19% of E. coli isolates were resistant to 3 or more of the analyzed antimicrobial agents, and 9% were regarded as multiple-antibiotic-resistant (MAR) strains. Two of the analyzed isolates were regarded as extended-spectrum β-lactamase – producing strains.