Prevalence and treatment outcome of extensively drug-resistant tuberculosis plus additional drug resistance from the National Clinical Center for Tuberculosis in China: A five-year review

The objective of this study was to explore the prevalence and primary clinical outcomes of extensively drug-resistant tuberculosis plus addition resistance to all drug tested (XDR-TB-Plus) between 2011 and 2015 in Beijing Chest Hospital.We retrospectively reviewed the drug susceptibility testing (DST) results of clinical Mycobacterium tuberculosis (MTB) strains from TB patients seeking health care in the National Clinical Center for Tuberculosis, between 2011 and 2015. The medical records of patients classified as XDR-TB-Plus were reviewed, including demographic characteristics, treatment regimen, and treatment outcome.Of 9544 MTB isolates, there were 3376 (35.4%), 842 (8.8%) and 61 (0.64%) isolates identified as multidrug resistant tuberculosis (MDR-TB), extensively drug resistant tuberculosis (XDR-TB) and XDR-TB-Plus, respectively. The proportion of XDR-TB showed significant increase from 6.3% in 2011 to 9.1% in 2015 (Chi-square trend 5.94, P = 0.015). Similarly, the proportion of XDR-TB-Plus seemed to increase from 0.46% in 2011 to 0.74% in 2015, while the increasing trend was not significant (Chi-square trend 1.50, P = 0.221). The most frequently prescribed anti-TB drug was moxifloxacin (18/29, 62.1%), followed by protionamide (16/29, 55.2%), clofazimine (15/29, 51.7%), and pyrazinamide (15/29, 51.7%). Patients receiving regimens containing linezolid (LZD) were almost 27 times more likely to have favorable treatment outcome compared with those receiving regimens without LZD [odds ratios = 27.00; 95% CI = 2.50-291.19; P = 0.003].In conclusion, our data have demonstrated that the proportion of XDR-TB has significantly increased over the past five years in Beijing Chest Hospital. In addition, the XDR-TB-Plus patients were more likely to reach favorable clinical outcome under the treatment of regimen containing LZD.