Fig 4.

Positivity for additional biomarkers for the diagnosis of LTBI in 69 HCW after RD1 stimulation. Cytokine secretion is shown as a heat map, with each row representing the cytokine concentrations in individual HCW. Only cytokines for which a significant difference was observed between the LTBI-positive and LTBI-negative groups after adjustment for multiple comparisons are represented. Adjusted P values are shown below the heat map. HCW are ranked according to cytokine concentrations and TST and QFT test results. For each parameter, an appropriate color was assigned ranging from white, representing the lowest values (TST, ≤5 mm; QFT, <0.1 IU/ml; cytokine concentrations less than the median of the LTBI-negative group), to black, symbolizing the highest values (TST, >20 mm; QFT, greater than or equal to the median of those of the LTBI-positive group, i.e., 1.055 IU/ml; cytokine concentrations greater than or equal to the median of those of the LTBI-positive group), passing by light gray (TST [5 to 10] mm, QFT [0.1 to 0.35] IU/ml, and cytokine concentrations [the median in the LTBI-negative group to the cytokine thresholds]) and dark gray (TST [10 to 20] mm, QFT [0.35 to the median in the LTBI-positive group, i.e., 1.055 [IU/ml, and cytokine concentrations [the cytokine thresholds to the median in the LTBI-positive group]). The second-look LTBI diagnosis was done using IL-15 and MIG measurements after the QFT assay and previously defined thresholds.