Table 4. Clinical information of subjects with discordant CLIA-IGRA and QFT-GIT assay results.
| Subject | Age (yr)/ sex | BCG vaccination | TST induration (size) | CLIA-IGRA result | CLIA-IGRA Ag-NC (IU/mL) | QFT-GIT assay result | QFT-GIT Ag-NC (IU/mL) | Additional information |
|---|---|---|---|---|---|---|---|---|
| 1 | 53/F | Yes | Negative (0 mm) | Negative | 0.29 | Positive | 0.87 | Newly diagnosed as having LTBI by QFT-GIT assay |
| 2 | 46/M | N/A | Positive (12 mm) | Negative | 0.30 | Positive | 1.07 | Normal X-ray |
| 3 | 22/F | Yes | Positive (15 mm) | Negative | 0.26 | Positive | 3.59 | Recovering from recent active TB AFB, PCR negative |
Abbreviations: M, male; F, female; BCG, Bacillus Calmette-Guérin; TST, tuberculin skin test; Ag, antigen; ANC, negative control; TB, tuberculosis infection; AFB, acid-fast stain; N/A, not available; CLIA-IGRA, chemiluminescent immunoanalyzer-based interferon gamma releasing assay; QFT-GIT, QuantiFERON-TB Gold In-Tube; LTBI, latent tuberculosis infection.