Interferon-γ Release Assay Performance for Tuberculosis in Childhood

Background Interferon-γ release assays (IGRAs) are important adjunctive tests for diagnosing tuberculosis (TB) disease in children. Methods We analyzed California TB registry data for patients ≤18 years with laboratory-confirmed TB disease during 2010-2015 to identify case characteristics associated with test selection and performance and measure IGRA sensitivity. Results In total, 778 cases of TB were reported; 360 were laboratory confirmed. Indeterminate IGRAs were associated with being P = .01); IGRA sensitivity compared with TST in children ages 2 to 4 was 91% (10 out of 11) vs 91% (10 out of 11) ( P > .99), and the sensitivity compared with TST in children aged P > .99). Conclusions This is the largest North American analysis of IGRA use and performance among children with TB disease. In children <5 years old, IGRA sensitivity is similar to TST, but sensitivity of both tests are reduced in children <2 years old. Indeterminate results are higher in children <1 year old and in central nervous system disease. In children ≥5 years old with laboratory-confirmed TB, IGRA has greater sensitivity than TST and should be considered the preferred immunodiagnostic test..