Tuberculosis that is “resistant to all drugs”: frequently asked questions

In 2006, the first reports of extensively drug-resistant tuberculosis (XDR-TB), even more severe than multidrug-resistant TB (MDR-TB), began to appear. Within a year of the first reports of XDR-TB, isolated cases were reported in Europe that had resistance to all first-line and second-line anti-TB drugs that were tested. In 2009, a cohort of 15 patients in the Islamic Republic of Iran was reported to be resistant to all anti-TB drugs tested. The terms extremely drug-resistant (XXDR) and totally drug-resistant TB (TDR-TB) were used by the authors reporting this group of patients. Recently, another study has been published that describes 4 patients from India with resistance to all tested drugs.

WHO's Stop TB Department has just published a briefing note with frequently asked questions, to provide information on TB that is resistant to all drugs.