Epidemiology and clinical characteristics of childhood TB identified using active and passive case finding

BACKGROUND: Childhood TB cases can be found using passive case finding (PCF), i.e., by diagnosing children presenting with symptoms, or using active case finding (ACF), i.e., by identifying children with TB through contact tracing. Our study determined epidemiologic, clinical, and radiographic differences between these groups.DESIGN/METHODS: Retrospective cohort study of children aged 0-19 years diagnosed with TB from January 1, 2012 to December 31, 2019 at a U.S. TB clinic, comparing clinical, radiographic, microbiologic, and epidemiological characteristics of children identified using PCF and ACF.RESULTS: Of 178 eligible patients, 99 (55.6%) were diagnosed using PCF. Children identified using PCF were older (mean 8.9 vs. 6.1 years, P = 0.003), more often non-US-born (OR 2.29, 95% CI 1.12-4.67), had more extrapulmonary disease (44.4% vs. 3.8%, OR 20.27, 95% CI 5.98-68.64) and severe intrathoracic findings (39.4% vs. 10.1%, OR 5.77, 95% CI 2.50-13.29). Children identified using ACF were often asymptomatic, had isolated hilar/mediastinal adenopathy, but had more availability of drug susceptibility data from a link to a source case.CONCLUSION: Children identified using PCF had more severe manifestations, while those identified using ACF had greater availability of drug susceptibility data. Clinicians should be aware that clinical and radiographic presentations in children identified using PCF and those identified using ACF differ, and that the latter may be eligible for shorter treatment regimens.