Study population
To this prospective study we recruited children aged < 18
years admitted to the Children’s Hospital, Medical University of Warsaw,
Poland, and Mazovian Centre for Treatment of Lung Diseases and
Tuberculosis, Otwock, Warsaw Agglomeration, Poland between May 2012 and
September 2015. Eligible for participation were 1) children with
clinical suspicion of TB and 2) children in recent contact with
pulmonary TB (PTB). Exclusion criteria included immunosuppression,
previous antituberculous treatment, and TST performed within the last 18
months to minimize the risk of boosting. Ethics approval for this study
was provided by the Bioethical Committee of the Medical University of
Warsaw and written informed consent was obtained from the legal guardian
of each participant before enrollment.