Table 1.
The Diagnostic Accuracy of AFB Smear and TB-RNA for Rapid Pulmonary Tuberculosis Diagnosis in Various Respiratory Specimens
| Test | Total PTB | Sputum | BALF | P value |
|---|---|---|---|---|
| AFB smear | ||||
| Sensitivity (%) | 36.2 (34.0–38.5) | 44.5 (41.1–47.9) | 29.2 (26.4–32.1) | < 0.001 |
| Specificity (%) | 86.4 (83.1–89.3) | 81.5 (76.6–85.9) | 92.7 (88.5–95.8) | < 0.001 |
| PPV (%) | 90.6 (88.2–92.6) | 87.5 (84.0–90.5) | 94.8 (91.7–97.0) | 0.001 |
| NPV (%) | 27.3 (25.1–29.5) | 33.5 (30.0–37.2) | 22.5 (19.8–25.4) | < 0.001 |
| AUC | 0.61 (0.59–0.63) | 0.63 (0.60–0.66) | 0.61 (0.58–0.64) | 0.445 |
| TB RNA | ||||
| Sensitivity (%) | 57.4 (55.1–59.7) | 49.6 (46.2–53.1) | 63.9 (60.9–66.9) | < 0.001 |
| Specificity (%) | 99.4 (98.3–99.9) | 99.3 (97.5–99.9) | 99.5 (97.5–100.0) | 0.724 |
| PPV (%) | 99.7 (99.2–99.9) | 99.5 (98.3–99.9) | 99.8 (99.1–100.0) | 0.337 |
| NPV (%) | 39.3 (36.6–42.0) | 40.4 (36.7–44.1) | 38.0 (34.0–42.1) | 0.379 |
| AUC | 0.78 (0.77–0.80)* | 0.74 (0.72–0.77)* | 0.82 (0.79–0.84)* | < 0.001 |
Notes: P values represent the difference between sputum and BALF. The difference between TB-RNA and AFB smear, *P < 0.001.
Abbreviations: PTB, pulmonary tuberculosis; BALF, bronchoalveolar lavage fluid; AFB, acid-fast bacillus; TB-RNA, Mycobacterium tuberculosis RNA; PPV, positive predictive value; NPV, negative predictive value; AUC, area under the curve.