IMPACT OF BASELINE TUBERCULIN SKIN TEST AND ISONIAZID CHEMOPROPHYLAXIS ON SUBSEQUENT QUANTIFERON-TB GOLD IN-TUBE PERFORMANCE IN YOUNG CHILDREN ASSESSED AFTER TUBERCULOSIS CONTACT IN CATALONIA.

We investigated the impact of baseline tuberculin skin tests (TSTs) and preventive isoniazid chemoprophylaxis on subsequent QuantiFERON-TB Gold In-Tube (QFT-GIT) assays performed after a 10- to 12-week window period in 114 children <5 years of age. Previous TSTs and chemoprophylaxis had no impact on the magnitude of subsequent antigen-induced responses in QFT-GIT. Furthermore, previous TSTs did not induce conversion from a negative to a positive QFT-GIT result.