Multi drug Resistant  Enteric fever: 

Resistance  against first line agents:ampicillin,chloramphenicol, co- trimoxazole, with or with out resistance to flouroquinolones. 

Extended drug resistant enteric fever:

Resistance against first line agents:ampicillin, chloramphenicol, co trimoxazole, flouroquinolones  and third generation cephalosporins.