XDR-TB is defined as:: (A) Resistance to at least INH & rifampicin +/- other drugs, (B) Resistance to any of the 3 first line drugs, (C) Resistance to all 1st line drugs & any 3 second line injectable drugs, (D) Resistance to at least INH & rifampicin + any quinolones + at least 1 injectable 2nd line drug
Answer is D. XDR -TB - resistant to - (1) INH & rifampicin (2) Any fluoroquinolone (3) 1 of 3 injectable drug (Amikacin, kanamycin or Capreomycin) MDR-TB - Resistance to INH & Rifampicin.