Performance and correlation of QuantiFERON-TB Gold, T-SPOT.TB and tuberculin skin test in young children with or exposed to tuberculosis

Objective:To evaluate the performance of interferon gamma release assays and tuberculin skin test in Bacillus Calmette-Guerin vaccinated young children.Methods:A cross-sectional study was conducted in healthy children younger than 5 years who were recently diagnosed with tuberculosis or had recent exposure to active tuberculosis.QuantiFERON-TB Gold,T-SPOT.TB and tuberculin skin test were performed in each patient.Results:Of the 60 children,median age 3.3 years,17 had tuberculosis and 43 had recent tuberculosis exposure.Overall,15(25.0%)children had tuberculin skin test reaction≥10 mm;8(13.3%)were positive by QuantiFERON-TB Gold In-Tube test,and 12(20.0%)by T-SPOT.TB.Nineteen(31.7%)children had at least one positive test.There was a moderate agreement between interferon gamma release assays and tuberculin skin test.Conclusions:The positive rates of interferon gamma release assays and tuberculin skin test were low in young children who were infected with tuberculosis,supporting the management strategy of not testing children younger than 5 years.

Performance and correlation of interferon gamma release assays and tuberculin skin test in HIV-infected children and adolescents with immune reconstitution

Objective:To evaluate the performance of interferon gamma release assays and tuberculin skin test in HIV-infected children and adolescents with immune reconstitution.Methods:A cross-sectional study was conducted in HIV-infected patients aged 5-18 years receiving antiretroviral treatment with CD4 T-lymphocytes>25%or>500 cells/mm3 for at least 6 months.QuantiF ERON-TB Gold,T-SPOT.TB,and tuberculin skin test were performed in each patient.Results:A total of 50 patients were enrolled with median age of 13.7 years,CD4 counts of 753(IQR:587-989)cells/mm3.Among 27 patients with tuberculosis(16)or tuberculosis exposure(11),8(29.6%)were positive to at least one test,2(7.4%)were positive QuantiFERON-TB Gold,3(11.1%)positive T-SPOT.TB,and 7(25.9%)had tuberculin skin test≥5 mm.Among 23 patients without history of tuberculosis or exposure,all had negative interferon gamma release assays,while 2(8.7%)had positive tuberculin skin test.Conclusions:All tests had low sensitivity despite immune reconstitution.