Methods: A total of 76 Enterobacter isolates : 63 ESBL producing strains (32 E. aerogenes and 31 E. cloacae) and 13 non ESBL producing strains (7 E. aerogenes and 6 E. cloacae) were inoculated into the VITEK 2 AST-045 and AST-046 cards according to the manufacturer recommendations.