TABLE 2.
Performance of different diagnostic tests stratified by HIV status for the detection of tuberculosis (TB) in individuals negative for a single Xpert MTB/RIF test
| Performance in Xpert MTB/RIF
negative individuals#
|
||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| All patients¶
|
HIV uninfected+
|
HIV infected§
|
All patients¶
|
HIV uninfected+
|
HIV infected§
|
|||||||
| Sensitivity %f (95% CI) n/N |
Specificity %## (95% CI) n/N |
Sensitivity %f (95% CI) n/N |
Specificity %## (95% CI) n/N |
Sensitivity %f (95% CI) n/N |
Specificity %## (95% CI) n/N |
PPV (95% CI) n/N |
NPV (95% CI) n/N |
PPV (95% CI) n/N |
NPV (95% CI) n/N |
PPV (95% CI) n/N |
NPV (95% CI) n/N |
|
| Smear microscopy | 20.6 (10.4–36.8) 7/34 |
99.4 (97.7–99.8) 314/316 |
25 (10.2–49.5) 4/16 |
99.5 (97.1–99.9) 192/193 |
13.3 (3.7–37.9) 2/15 |
98.7 (92.9–99.8) 75/76 |
77.8 (45.3–93.7) 7/9 |
92.1 (88.7–94.5) 314/341 |
80.0 (37.6–96.4) 4/5 |
94.1 (90.0–96.6) 192/204 |
66.7 (20.8–93.9) 2/3 |
85.2 (76.4–91.2) 75/88 |
| CXR for active TB | 100 (86.2–100) 24/24 |
26.7 (21.1–33.0) 56/210 |
100 (72.3–100) 10/10 |
29.3 (22.0–37.8) 36/123 |
100 (77.2–100) 13/13 |
27.8 (17.6–40.9) 15/54 |
13.5 (9.2–19.3) 24/178 |
100 (93.6–100) 56/56 |
10.3 (5.7–18.0) 10/97 |
100 (90.4–100) 26/26 |
25 (15.2–38.2) 13/52 |
100 (79.6–100) 15/15 |
| Smear microscopy combined with CXR¶¶ | 100 (86.2–100) 24/24 |
26.7 (21.1–33.0) 56/210 |
100 (72.3–100) 10/10 |
29.3 (22.0–37.8) 36/123 |
100 (77.2–100) 13/13 |
27.8 (17.6–40.9) 15/54 |
13.5 (9.2–19.3) 24/178 |
100 (93.6–100) 56/56 |
10.3 (5.7–18.0) 10/97 |
100 (90.4–100) 26/26 |
25 (15.2–38.2) 13/52 |
100 (79.6–100) 15/15 |
| T-SPOT.TB | 74.1 (55.3–86.8) 20/27 |
43.4 (37.1–49.9) 98/226 |
73.3 (48.1–89.1) 11/15 |
33.1 (25.8–41.3) 46/139 |
77.8 (45.3–93.7) 7/9 |
63.6 (50.4–75.1) 35/55 |
13.5 (8.9–20.0) 20/148 |
93.3 (86.9–96.7) 98/105 |
10.6 (6.0–18.0) 11/104 |
92 (81.2–96.9) 46/50 |
25.9 (13.2–44.7) 7/27 |
94.6 (82.3–98.5) 35/37 |
| QFT-GIT | 80.0 (60.9–91.1) 20/25 |
41.0 (34.9–47.5) 94/229 |
84.6 (57.8–95.7) 11/13 |
34.9 (27.8–42.7) 53/152 |
77.8 (45.3–93.7) 7/9 |
60.5 (45.6–73.6) 26/43 |
12.9 (8.5–19.1) 20/155 |
94.9 (88.7–97.8) 94/99 |
10 (5.7–17.0) 11/110 |
96.4 (87.7–99.0) 53/55 |
29.2 (14.9–49.2) 7/24 |
92.9 (77.4–98.0) 26/28 |
PPV: positive predictive value; NPV: negative predictive value; CXR: chest radiograph; QFT-GIT: QuantiFERON-TB Gold In-Tube (Cellestis, Chadstone, Australia). T-SPOT-TB is manufactured by Oxford Immunotec Ltd, Oxford, UK.
liquid culture positivity for Mycobacterium tuberculosis served as a reference standard.
n=5350.
n=5209, 50 individuals were of unknown HIV status (test refused or data missing).
n=591, 50 individuals were of unknown HIV status (test refused or data missing).
calculated by dividing the number of MTB/RIF-negative individuals positive for the adjunct test(s) by the number of MTB/RIF-negative, culture-positive individuals who had received the same adjunct test(s); not all individuals received the same combination of tests.
calculated by dividing the number of MTB/RIF-negative, culture-negative individuals negative for the adjunct test(s) by the number of MTB/RIF-negative, culture-negative individuals (i.e. both probable and non-TB groups were included) who had received the same adjunct test(s); not all individuals received the same combination of tests.
performed if smear negative.