[Antibiotic resistance in Escherichia coli O157 isolated between 1998 and 2003 in The Netherlands].

Little is known about the antibiotic resistance of E. coli O157 in The Netherlands. In this study, 218 human and 247 nonhuman samples, isolated between 1998 and 2003, were tested for antimicrobial resistance. About 5.5% of E. coli O157 isolates from human samples were resistant, as were about 4.00% of E. coli O157 isolates from non-human samples. These figures are lower than those reported in the literature. Class I integrons were found in six multiresistant isolates. This type of integron is also found in commensal E. coli in food animals and Salmonella spp. One of the integron-positive isolates contained the beta-lactamase bla(TEM-1b) and an extended spectrum beta-lactamase (ESBL), which belongs to the group 2 CTX-M enzymes. This is the first report of these beta-lactamases in E. coli O157 isolated from chicken.