The epidemiological characteristics and profile of drug-resistant tuberculosis among children with tuberculosis in Sichuan, China, 2015-2018: A retrospective study

Abstract

Background: The aim of this study was to investigate the epidemiological characteristics and profile of drug-resistant tuberculosis (DR-TB) among children with TB in Sichuan province of China.Methods: From January 2015 to December 2018, microbiological culture-confirmed child TB cases (aged<15 years old) were enrolled retrospectively. Epidemiological and clinical information from these cases, and the drug susceptibility testing (DST) results of the isolates were collected and analyzed.Results: Of 317 culture-confirmed child TB cases, 16.7% (53/317) were aged under 5 years old. 54.9% were Tibetans, and 31.9% had clear history of contact with TB patients. More than half (53.9%) weren’t vaccinated by Calmette–Guérin bacillus (BCG). 30% (n=95) were diagnosed as severe TB, and 92.4% (n=293) were new cases. The ratio of severe TB in BCG vaccinated group was significant lower than that observed in unvaccinated group (p<0.01). Significantly higher proportion of severe TB among Tibetans than Han child TB cases was observed in BCG unvaccinated group (p<0.01). The overall rate of DR-TB in this study was 24.3% (77/317) and 17 multidrug-resistant tuberculosis (MDR-TB) cases were identified with rate of MDR-TB at 5.4% (17/317). No XDR case was found. 13 out of 17 MDR-TB cases (76.4%) were Tibetan children. The ratio of any resistance to four first-line drugs identified were: INH, 15.5%; RIF, 9.1%; EMB, 0.6% and SM, 6.0%, respectively. More than half of MDR patterns were resistant to INH+RIF (9/17), followed by at least resistance to INH+RIF+SM (n=7). Conclusions: This was the first investigation on the epidemiological characteristics and profiles of DR-TB among child TB cases in Southwest of China. Our findings indicated a potentially high risk of TB infection to Tibetan children in the concentrated Tibetan communities of Sichuan.