Childhood tuberculosis (TB) is a major infectious disease causing morbidity and mortality in children and yet has been largely ignored until recently. This study is the first study to characterize childhood TB in China incorporating both Mycobacterium tuberculosis genetic characteristics and patient data.
We analyzed a total of 331 culture-confirmed childhood TB cases and 158 M. tuberculosis isolates from a subset of the study sample. Univariate and multivariate logistic regression analyses were performed to identify host and microbial predictors for having extrathoracic TB alone, concurrent thoracic and extrathoracic TB and TB meningitis (TBM), respectively.
Fifty-eight percent (192/331) of the study subjects had extrathoracic TB, and 139 (42.0%) cases had TBM. Both age of less than 5 years [adjusted odds ratio (OR): 4.52; 95% confidence interval (CI): 1.27–16.16] and female sex (adjusted OR: 2.72; 95% CI: 1.03–7.18) were significantly associated with extrathoracic TB alone, whereas living in rural area (adjusted OR: 2.35; 95% CI: 1.06–5.18) was significantly associated with thoracic–extrathoracic TB. Age of less than 5 years was also strongly associated with TBM (adjusted OR: 3.63; 95% CI: 1.64–8.05). Sixty-four percent (101/158) of the study isolates were Beijing lineage strains. Infection with Beijing lineage strains was significantly associated with thoracic–extrathoracic TB (adjusted OR: 2.39; 95% CI: 1.11–5.15) and TBM (adjusted OR: 2.25; 95% CI: 1.10–4.60).
Both microbial and host factors can affect the outcome of M. tuberculosis infection in children. Future studies incorporating host and pathogen data from different populations are warranted to develop new strategies for childhood TB control.
From the *Department of Infectious Diseases, Children’s Hospital of Chongqing Medical University, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing, China; †Epidemiology Department, School of Public Health, University of Michigan, Ann Arbor, Michigan.
Accepted for publication July 28, 2015.
The authors have no conflicts of interest to disclose. This study was supported by a grant from the Scientific Research Foundation of Chongqing Municipal Health Bureau (2008-2-177).
Zhenhua Yang and Chaomin Zhu contributed equally to this work.
Address for correspondence: Chaomin Zhu, MD, Department of Infectious Diseases, Children’s Hospital of Chongqing Medical University, 136 the Second Zhongshan Road, Yuzhong District, Chongqing 400014, China. E-mail: firstname.lastname@example.org; Zhenhua Yang, MD, PhD, Epidemiology Department, School of Public Health, University of Michigan, M5124/SPH II, 1415 Washington Heights, Ann Arbor, MI 40109-2029. E-mail: email@example.com.