Table 1.
General characteristics of specimens used in evaluating the smear microscopy, Xpert G4, Xpert Ultra and LPA assays.
| Category | Pulmonary samples | Extra-pulmonary samples | Total | Cumulative total |
|---|---|---|---|---|
| Specimen type | ||||
| Sputum | 117 | NA | 117 | 117 |
| abscess | NA* | 4 | 4 | 121 |
| csf | NA | 3 | 3 | 124 |
| Fluid/ aspirate | NA | 18 | 18 | 142 |
| swab (superficial) | NA | 4 | 4 | 146 |
| Tissue | NA | 15 | 15 | 161 |
| tracheal/aspirate | 8 | NA | 8 | 169 |
| urine | NA | 36 | 36 | 205 |
| Total | 125 | 80 | 205 | 205 |
| Culture results | ||||
| Culture Contaminated | 3 | 0 | 3 | 3 |
| Culture positive | 50 | 13 | 63 | 66 |
| Culture negative | 72 | 67 | 139 | 205 |
| Total | 125 | 80 | 205 | 205 |
| Auramine smear microscopy results | ||||
| Smear (auramine) positive | 51 | 8 | 59 | 59 |
| Smear (auramine) negative | 74 | 72 | 146 | 205 |
| Total | 125 | 80 | 205 | 205 |
| Xpert Ultra results | ||||
| Xpert Ultra positive (TB detected) | 76 | 43 | 119 | 119 |
| Xpert Ultra negative (TB undetected) | 47 | 37 | 84 | 203 |
| Xpert Ultra Invalid | 2 | 0 | 2 | 205 |
| Total | 125 | 80 | 205 | 205 |
| Ultra G4 results | ||||
| Xpert G4 positive (TB detected) | 49 | 8 | 57 | 57 |
| Xpert G4 negative (TB undetected) | 75 | 71 | 146 | 203 |
| Xpert G4 error | 1 | 0 | 1 | 204 |
| Xpert G4 invalid | 0 | 1 | 1 | 205 |
| Total | 125 | 80 | 205 | 205 |
| LPA results | ||||
| LPA positive (TB detected) | 107 | 59 | 166 | 166 |
| LPA negative (TB undetected) | 18 | 21 | 39 | 205 |
| Total | 125 | 80 | 205 | 205 |
| Breakdown of results under culture and smear microscopy categorisation | ||||
| Smear negative (SN)-Culture negative (CN) | 65 | 66 | 131 | 131 |
| Smear positive (SP)-Culture positive (CP) | 41 | 7 | 48 | 179 |
| SN-CP | 9 | 6 | 15 | 194 |
| SP-CN | 7 | 1 | 8 | 202 |
| Total | 122* | 80 | 202 * | 202* |