FIG 3.

Distribution of interferon gamma levels (TB antigen-minus-nil values) in the samples measured in the Standard E TB-Feron ELISA (TBF), the QuantiFERON-TB Gold In-Tube assay (QFT-GIT), and the two cross-manner tests (TBF tubes/QFT ELISA and QFT tubes/TBF ELISA). The dashed lines designate the cutoff values for the determination of positive results from the IGRAs (0.35 IU/ml). (A) Results for samples which showed positivity by TBF but negativity by QFT-GIT (n = 6); (B) results for samples which had negative results by TBF but positive results by QFT-GIT (n = 13).