Interferon-gamma release assay sensitivity in children younger than 5 years is insufficient to replace the use of tuberculin skin test in western countries

Tuberculin skin test, QuantiFERON-TB Gold In-Tube and T-SPOT.TB were performed in 338 children at risk for tuberculosis (TB), including 70 active TB cases. In children <5 years of age, QuantiFERON-TB Gold In-Tube sensitiv- ity was 73.3% [95% confidence interval (CI): 57.5–89.1]; and T-SPOT.TB sensi- tivity was 59.3% (95% CI: 40.1–77.8); both were inferior to tuberculin skin test sensitivity (90.0%; 95% CI: 79.3–100). In children ≥5 years QuantiFERON-TB Gold In-Tube sensitivity was 92.5% (95% CI: 84.4–100); T-SPOT.TB sensitivity was 73.0% (95% CI: 58.6–87.3) ; and tuberculin skin test sensitivity was 97.5% (95% CI: 92.6–100).Test specificities were similar in all age groups.