NCIt definition : Any strain of Escherichia coli that is resistant to penicillins, cephalosporins, and
aztreonam. These strains are often cross-resistant to trimethoprim/sulfamethoxazole
and quinolones.;
Alternative definition : CDISC: Any bacterial organism that can be assigned to the species Escherichia coli
and produces extended-spectrum beta-lactamases (ESBL).;