A new study of tuberculosis patients in South Korea is filling in some of the blanks about extensively drug-resistant tuberculosis (XDR-TB), showing just how much more deadly and difficult to treat it is than TB caused by less-resistant strains (Kim DH et al. Am J Respir Crit Care Med. 2008;178:1075-1082).
The new findings are based on a review of medical records from 1407 patients who were newly diagnosed or retreated for multidrug-resistant tuberculosis (MDR-TB), which is caused by isolates resistant to the 2 most effective first-line drugs, isoniazid and rifampin. Only 1.5% of patients were also infected with HIV.
Voelker R. Findings From South Korea Provide Insight Into XDR-TB. JAMA. 2008;300(21):2475. doi:10.1001/jama.2008.773