Yield of QuantiFERON-TB gold in tube assay and tuberculin skin test in healthy persons from a tuberculosis endemic population

Abstract. We assessed the yield of the QuantiFERON-TB Gold in tube test (QFT-GIT) and the tuberculin skin test (TST) in healthy persons from our general population, where tuberculosis is endemic and Bacillus Calmette-Gu´erin is mandatory. The yield of QFT-GIT (2%) and TST (1%) were very low among children, where the test was positive in 42% and 24% of adults, respectively. Our study results show that QFT-GIT and TST are not influenced by prior Bacillus Calmette-Gu´erin vaccination. Applying the reduced cut-off point of 0.13 IU/mL is adequate in a pediatric population. Moreover, both the TST and the QFT-GIT demonstrated a low yield in the pediatric population, which suggests that either TST or QFT-GIT alone or in combination can be used to diagnose Mycobacterium tuberculosis infection in our setting