Prevalence and patterns of drug resistance among pulmonary tuberculosis patients in Hangzhou, China

BACKGROUND: To evaluate prevalence and patterns of drug resistance among pulmonary tuberculosis (TB) patients in Hangzhou City, China. METHODS: Sputum samples of smear positive TB patients enrolled in 2011 and 2015 were collected and tested for drug susceptibility, and demographic and medical record data were extracted from the electronic database of China Information System for Disease Control and Prevention. Chi-square test was used to compare drug resistance prevalence between new and treated patients and between male and female patients, and Chi-square test for trend was used to compare the prevalence over calendar years 2011 and 2015. RESULTS: Of 1326 patients enrolled in 2015, 22.3% had resistance to any first-line anti-TB drugs and 8.0% had multi-drug resistance (MDR); drug resistance rates among previously treated cases were significantly higher than among new cases. Significant declines of resistance to isoniazid, rifampin, ethambutol and streptomycin, and MDR from 2011 to 2015 were observed among previously treated patients, while a significant decline of resistance to rifampin was observed among new cases. CONCLUSIONS: While the prevalence of acquired drug resistance decreased due to due to implementation of DOTS-Plus program, the prevalence of primary drug resistance due to transmission remained high. Greater efforts should be made to screen drug resistance for case finding and to reduce transmission through improving the treatment and management of drug-resistant patients.