Table 3.
Performances of GeneLEAD/Deeplex Myc-TB assay and microscopic examination for the detection of M. tuberculosis complex in 112 specimens, in comparison with culture.
| MTBC culture result | MTBC identification by GeneLEAD | MTBC identification by Deeplex Myc-TB | Microscopic examination | |||
|---|---|---|---|---|---|---|
| Positive (n) | Negative (n) | Positive (n) | Negative (n) | Positive (n) | Negative (n) | |
| Positive | 58 | 0 | 46 | 12 | 42 | 16 |
| Negative | 5a,c,d | 49 b | 0 | 54a,b,c,d | 5a,b,c | 49 d |
| Sensitivity, % | 100 | 79.3 | 72.4 | |||
| [95% CI] | [100–100] | [71.8–86.8] | [64.1–80.7] | |||
| Specificity, % | 98 | 100 | 90.7 | |||
| [95% CI] | [95.4–100.6] | [100–100] | [85.3–96.1] | |||
| Cohen’s kappa | 0.91 | 0.79 | 0.63 | |||
| [95% CI] | [0.86–0.96] | [0.71–0.87] | [0.54–0.72] | |||
a
Including one sample growing M. chelonae/immunogenum.
b
Including three samples growing M. xenopi.
c
One sample with <1 AFB/field and >10 AFB/slide from a patient under treatment for active TB: not counted as false positive by GeneLEAD.
d
Three AFB-negative samples from patients under treatment for active TB: not counted as false positive by GeneLEAD.