Performance of the QuantiFERON-TB Gold Interferon Gamma Release Assay among HIV-Infected Children in Botswana

Interferon gamma release assays (IGRAs) are poorly studied in HIV-infected children. The authors prospectively evaluated QuantiFERON-TB Gold results and family-described tuberculosis (TB) risk factors in 100 HIV-infected children in Botswana. Median age was 10.2 years; 58 were girls, 92 had received the Bacillus Calmette–Guerin (BCG) vaccine, 98 were receiving antiretroviral therapy, and the median body mass index was 15.8 kg/m2. Eighty-nine children had undetectable viral loads and the median CD4 count was 962 cells/mm3. Eighteen children had been treated for TB in the last 3 years. In the last 3 years, 36 (including 9 with TB) had contact with persons with TB (26 within/15 outside the home and 5 had >1 contact). In all, 96 children had negative IGRAs, 3 were indeterminate, and 1 was positive. The positive IGRA was reported in a child treated for TB prior to 3 years. Interferon γ release assay positivity was rare in this pediatric cohort living in an area with a high prevalence of TB.