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What is XDR-TB is defined as: March 2012 and explain in detail?
Ans: D i.e. Resistance to atleast INH and rifampicin + any quinolones + atleast 1 injectable 2nd line drug Terminology related to drug therapy of TB MDR/ Multi Drug Resistant TB is defined by resistance to at least rifampicin and isoniazid, with or without other drug resistance Drug resistant TB is defined by the presence of resistance to any first line agent Extensively drug resistant (XDR) TB is defined by resistance to at least rifampicin and isoniazind, in addition to any quinolone and at least one injectable second line agent