Table 7. Sensitivity of the serology test using ELISA based on the PGL-Tb1 or the ESAT-6/CFP10 antigen and their cumulative results in the different groups of active TB enrolled patients stratified by HIV status and TB localization.
| Antigen | HIV status | n/N | Pulmonary ATB | n/N | Extrapulmonary ATB% | Pulmonary versus extrapulmonary | n/N | All ATB% |
| % (95% CI) | % (95% CI) | % (95% CI) | ||||||
| PGL-Tb1 * | Infected | 50/68 | 73.5 (61.4–83.5)*** | 23/34 | 67.7 (49.5–82.6)*** | P = 0.6423 | 73/102 | 72.3 (62.4–80.7)*** |
| Uninfected | 104/270 | 38.5 (32.7–44.6) | 13/46 | 28.3 (16.0–43.5) | P = 0.2472 | 117/316 | 37.0 (31.7–42.6) | |
| Unknown | 136/293 | 46.4 (40.6–52.3) | 22/67 | 32.8 (21.9–45.4) | P = 0.0556 | 158/360 | 43.6 (38.4–48.9) | |
| Uninfected +unknown | 240/563 | 42.6 (38.5–46.8) | 35/113 | 31.0 (22.6–40.4) | P = 0.0213 | 275/676 | 40.5 (36.8–44.3) | |
| Total | 290/631 | 46.0 (42.0–49.9) | 58/147 | 39.5 (31.5–47.8) | P = 0.1675 | 348/778 | 44.7 (41.2–48.3) | |
| ESAT-6/CFP10** | Infected | 42/68 | 61.8 (49.2–73.3)*** | 23/34 | 67.7 (49.5–82.6)*** | P = 0.6639 | 65/102 | 63.7 (53.6–78.0)*** |
| Uninfected | 82/270 | 30.4 (24.9–36.2) | 11/46 | 23.9 (12.6–38.8) | P = 0.4841 | 93/316 | 29.4 (24.5–34.8) | |
| Unknown | 89/293 | 31.0 (25.8–36.7) | 11/67 | 16.4 (8.5–27.5) | P = 0.0162 | 100/360 | 27.8 (23.2–32.7) | |
| Uninfected +unknown | 171/563 | 30.6 (26.8–34.5) | 22/113 | 19.5 (12.6–28.0) | P = 0.0169 | 193/676 | 28.6 (25.2–32.1) | |
| Total | 213/631 | 33.9 (30.2–37.8) | 45/147 | 30.6 (23.3–38.7) | P = 0.4966 | 258/778 | 33.2 (29.9–36.6) | |
| Both antigens | Infected | 52/68 | 76.5 (64.6985.9)*** | 25/34 | 73.5 (55.6–87.1)*** | P = 0.8088 | 77/102 | 75.5 (66.0–83.5)*** |
| Uninfected | 133/270 | 49.3 (43.2–55.4) | 20/46 | 43.5 (28.9–58.9) | P = 0.5248 | 153/316 | 48.4 (42.8–54.1) | |
| Unknown | 166/293 | 56.7 (50.8–62.4) | 25/67 | 37.3 (25.8–50.0) | P = 0.0045 | 191/360 | 53.1 (47.8–58.3) | |
| Uninfected +unknown | 299/563 | 53.1 (48.9–57.3) | 45/113 | 39.8 (30.7–49.5) | P = 0.0131 | 344/676 | 50.9 (47.1–54.7) | |
| Total | 351/631 | 55.6 (51.7–59.6) | 70/147 | 47.6 (39.3–56.0) | P = 0.0816 | 421/778 | 54.1 (50.5–57.7) |
Footnotes: TB: tuberculosis; HIV: human immunodeficiency virus; n/N = number of positive tests/number of tested sera in each group; * Cut-off value for PGL-Tb1: OD = 0.130; ** Cut-off value for ESAT-6/CFP10: OD = 0.100; *** HIV-infected versus HIV-uninfected or HIV-unknown: p<0.0001;