extensively drug-resistant tuberculosis (xdr) is a relatively rare type of multidrug-resistant tuberculosis. it is resistant to almost all drugs used to treat tb including the two best first-line drugs: isoniazid and rifampin. xdr is also resistant to the best second-line medications: fluoroquinolones and at least one of three injectable drugs (i. e. amikacin kanamycin or capreomycin).
what is extensively drug-resistant (xdr) tuberculosis?