Temporal trend of drug-resistant tuberculosis among Thai children during 2006-2021.

BACKGROUND

The prevalence of drug-resistant tuberculosis (DR-TB) in adults has stabilized in the past decade. Our study aimed to describe the prevalence of DR-TB in Thai children between 2006 and 2021.

MATERIALS AND METHODS

Children younger than 15 years old who had culture-confirmed complex (MTB), positive PCR-MTB, or positive Xpert MTB/RIF were included in this cohort. Drug susceptibility testing (DST) was performed using phenotypic and/or genotypic methods. The prevalence of DR-TB was compared using the chi-square test.

RESULTS

Among 163 confirmed TB cases (44% as pulmonary TB, 27% as extrapulmonary TB, and 29% with both), the median age (IQR) was 12.2 (7.3-14.2) years. DST was performed in 139 cases (85%), revealing prevalences of all DR-TB, isoniazid-resistant TB (Hr-TB), and rifampicin monoresistant/multidrug-resistant TB (Rr/MDR-TB) of 21.6% (95% CI 14.7-28.4), 10.8% (95% CI 5.6-16.0%), and 2.9% (95% CI 0.1-5.7%), respectively. The DR-TB rates did not differ significantly between 2006-2013, 2014-2018, and 2019-2021 ( > 0.05). Two pre-extensively DR-TB (pre-XDR) cases with fluoroquinolone resistance were detected after 2014.

CONCLUSION

The prevalence of DR-TB in Thai children was stable. However, one-tenth of DR-TB cases confirmed with DST were Hr-TB, which required adjustment of the treatment regimen. The pre-XDR cases should be closely monitored.