Table 2: Proportion (in Percentage) of IGRA Indeterminate and Positive Results in Groups of HIV-Infected Patients with Active Tuberculosis and in HIV-Positive Patients without Tuberculosis Tested with TST, T-SPOT-TB and QuantiFERON –TB

Reference Diagnosis Number Subjects Mean CD4+/µL Tests
IGRA
TST SPOT QF-TB Indeterminate
Vincenti (Italy) [36] Active TB 45 152 47.0 84.6 84.6 20.0
Non TB 66 236 39.9 35.7 25.0 18.2
Rangaka (South Africa) [37] Active TB 41 167 67.0 90.0 90.0 12.2
Non TB 41 464 51.0 75.0 79.0 7;3
HIV (-) controls 41 NA* 69.0 83.0 83.0 0.0
Clark (UK) [38] Active TB 154 209 NT** 90.3 NT** 4.5
LTBI 47 294 NT** 20.0 NT** 4.5

* NA: non applicable.
** NT: non tested.