摘要
Dear Editor The prevalence of multidrug-resistant Mycobacterium tuberculosis （M. tuberculosis） is an increasing problem worldwide （Zumla et al., 2013; Dong et al., 2015）. According to a 2014 World Health Organization （WHO） report, 480,000 individuals world-wide .developed multidrug-resistant tuber- culosis （MDR-TB） and more than 100 countries have cases of extensively drug-resistant tuberculosis （XDR-TB）. Com- pared with drug-susceptible TB, MDR-TB and XDR-TB require prolonged therapeutic treatment with a combination of a number of second-line drugs （Chen et al., 2013）. For patients where TB remains persistent despite prolonged therapy with second-line TB drugs, the add-on agents including bedaquiline and delamanid are recommended for salvage therapy （GUnther, 2014; WHO, 2014; Shim and Jo, 2013）.
Dear Editor The prevalence of multidrug-resistant Mycobacterium tuberculosis （M. tuberculosis） is an increasing problem worldwide （Zumla et al., 2013; Dong et al., 2015）. According to a 2014 World Health Organization （WHO） report, 480,000 individuals world-wide .developed multidrug-resistant tuber- culosis （MDR-TB） and more than 100 countries have cases of extensively drug-resistant tuberculosis （XDR-TB）. Com- pared with drug-susceptible TB, MDR-TB and XDR-TB require prolonged therapeutic treatment with a combination of a number of second-line drugs （Chen et al., 2013）. For patients where TB remains persistent despite prolonged therapy with second-line TB drugs, the add-on agents including bedaquiline and delamanid are recommended for salvage therapy （GUnther, 2014; WHO, 2014; Shim and Jo, 2013）.
