IN-VITRO ACTIVITY OF LORACARBEF AGAINST TEM EXTENDED-SPECTRUM BETA-LACTAMASE-PRODUCING ESCHERICHIA-COLI STRAINS AND ITS INTERACTION WITH THE ENZYMES

The in vitro activity of loracarbef was evaluated against Escherichia coli strains producing TEM extended-spectrum beta-lactamases (ESBLs). The MICs of loracarbef were lower than those of cefaclor and cephaloth in. The antibiotic was active (MICs less than or equal to 2 mg/l) agai nst strains producing TEM-6, TEM-8, TEM-10, TEM-16, TEM-26 and TEM-28 beta-lactamases. The MICs for TEM-3-, TEM-5- and TEM-24-producing stra ins were higher (greater than or equal to 16 mg/l). Hydrolysis studies indicated that the latter beta-lactamases inactivated loracarbef more efficiently than the remaining TEM-type ESBLs examined.