Risk factors for Mycobacterium tuberculosis infection in Indonesian children living with a sputum smear-positive case.

SETTING AND OBJECTIVES Young children living with infectious tuberculosis (TB) cases are at high risk of infection and disease, and screening is recommended. This is rarely conducted in resource-limited settings. Identifying children most at risk of infection may be useful for setting practical screening policies. DESIGN Child contacts of smear-positive adult TB patients were invited for Mycobacterium tuberculosis infection and disease screening by symptoms, tuberculin skin test (TST), QuantiFERON-TB Gold In-Tube assay (QFT-GIT) and chest X-ray. Risk factors for infection were collected using a questionnaire and were calculated separately for TST, for QFT-GIT and for both tests combined. RESULTS Of 304 screened children 145/302 (48%) were positive using TST, 152/299 (51%) by QFT-GIT and 180/304 (59%) were positive using either or both tests. Positivity for both tests was associated with index case infectivity (acid-fast bacilli [AFB] 3+ vs. AFB 1+: TST OR 2.93, 95%CI 1.59-5.39; QFT-GIT OR 2.28, 95%CI 1.06-4.90) and exposure (child contact's parent is the index case: TST OR 7.04, 95%CI 2.23-22.28; QFT-GIT OR 4.30, 95%CI 1.48-12.45). CONCLUSION M. tuberculosis infection according to either test was high, supporting screening and preventive treatment. Children of smear-positive TB cases who accompany their parents to the clinic should be prioritised for immediate screening.