QuantiFERON®-TB Gold In-Tube for the detection of Mycobacterium tuberculosis infection in children with household tuberculosis contact

SETTING: Improved strategies are needed for detecting Mycobacterium tuberculosis infection in children in TB-endemic settings.OBJECTIVE: To determine the prevalence of M. tuberculosis infection by tuberculin skin testing (TST) and by the QuantiFERON®-TB Gold In-Tube (QFT-GIT) test in children with an adult household contact with pulmonary TB in South Africa.DESIGN: Cross-sectional study.RESULTS: A total of 167 adult pulmonary TB cases (153/167, 92% human immunodeficiency virus [HIV] infected) and 270 pediatric contacts (median age 6 years, 14/270, 5% HIV-infected) were enrolled. All children completed QFT-GIT testing and 254 (94.1%) completed TST testing. Prevalence of M. tuberculosis infection was 28% (71/254, 95%CI 23-34) using TST (5 mm cut-off) and 29% (79/270, 95%CI 24-35) using QFT-GIT (P = 0.49). Agreement between TST and QFT-GIT was 81% (kappa 0.58). Nineteen (7%) QFT-GIT results were indeterminate. Children aged