Tables
- TABLE 1
QuantiFERON-TB Plus (QFT-Plus) performance characteristics in different study groups
Frequency QFT-Plus result Positive results in each tube IFN-γ concentration¶ IU·mL−1 TB2−TB1 IU·mL−1 Indeterminate Negative# Positive# TB1 TB2 TB1 TB2 Low-risk controls 106 0 103 (97.17) 3 (2.83) 2 1 0.1 (0.09–0.13) 0.11 (0.09–0.13) 0 (−0.01–0.01) Active TB 119 3 14 (12.07) 102 (87.93) 96 101 2.09 (0.83–6.52) 2.88 (1–7.89) 0.14 (−0.13–0.79) Sex Male 72 1 7 (9.86) 64 (90.14) 59 64 2.08 (0.86–6.38) 2.91 (1.17–7.62) 0.23 (−0.14–0.88) Female 47 2 7 (15.56) 38 (84.44) 37 37 2.09 (0.71–7.03) 2.85 (0.88–7.80) 0.11 (−0.11–0.50) Smear Negative 65 1 12 (18.75) 52 (81.25) 51 52 2.12 (0.89–9.51) 2.69 (1.01–9.66) 0.05 (−0.17–0.55) Positive 54 2 2 (3.85) 50 (96.15) 45 49 2 (0.67–6.04) 3.26 (0.92–6.31) 0.29 (0–1.16) Localisation PTB 79 3 9 (11.84) 67 (88.16) 62 66 1.93 (0.57–6.04) 2.82 (0.75–6.22) 0.26 (−0.12–0.80) EPTB 40 0 5 (12.5) 35 (87.5) 34 35 2.29 (1.23–10) 2.95 (1.15–10) 0.06 (−0.17–0.46) BCG Negative 6 0 2 (33.33) 4 (66.67) 4 4 1.15 (0.33–1.86) 1.47 (0.4–2.75) 0.07 (0.01–0.44) Positive 54 0 4 (7.41) 50 (92.59) 44 50 2.01 (0.9–6.57) 2.79 (1.02–8.2) 0.14 (−0.20–0.65) Data are presented as n, n (%) or median (interquartile range). IFN: interferon; TB: tuberculosis; PTB: pulmonary tuberculosis; EPTB: extrapulmonary tuberculosis; BCG: bacille Calmette–Guérin. #: percentages are based on the total number of valid tests, excluding indeterminate results.