Extensively drug-resistant (XDR) tuberculosis (TB) is defined as TB that is resistant to at least rifampin and isoniazid (multidrug resistant [MDR]), as well as to any member of the quinolone family and at least one second-line anti-TB injectable drug: kanamycin, capreomycin, or amikacin. According to the World Health Organization (WHO), XDR-TB has been reported in 57 countries and is a major concern for global health. The WHO Global Task Force on XDR-TB has recommended laboratory-based surveillance to better understand the prevalence of XDR TB in developing countries. However, surveillance data on XDR-TB from China remain scarce. Shandong Province is the second largest province in China, with a population of 94 million. Shandong Provincial Chest Hospital (SPCH) is the only provincial-level hospital specializing in TB clinical service and control. In collaboration with the SPCH TB reference laboratory, researchers retrospectively analyzed the drug-resistance profiles of a group of clinical Mycobacterium tuberculosis isolates to estimate the prevalence of XDR-TB in China.
32% of isolates resistant to more than one first-line drug; 10% isolates were multidrug resistant, and 2% were XDR. XDR-TB is of major concern in China.
Laboratory-based Surveillance of Extensively Drug-Resistant Tuberculosis, China. EID 17(3) March 2011
To estimate the prevalence of extensively drug-resistant tuberculosis (XDR TB) in China, we retrospectively analyzed drug-resistance profiles of 989 clinical Mycobacterium tuberculosis isolates. We found 319 (32.3%) isolates resistant to >1 first-line drugs; 107 (10.8%) isolates were multidrug resistant, of which 20 (18.7%) were XDR. XDR TB is of major concern in China.