Table 2. Laboratory test results of participants diagnosed with TB, by type of test and specimen type (n = 88)*.
| Specimen | ZN Result† | FM Result† | Xpert MTB/RIF Result† | MGIT Result† | |||||
|---|---|---|---|---|---|---|---|---|---|
| Negative n (%; 95% CI)§ | Positive n (%; 95% CI)§ | Negative n (%; 95% CI)§ | Positive n (%; 95% CI)§ | Negative n (%; 95% CI)§ | Positive n (%; 95% CI)§ | Negative‡ n (%; 95% CI)§ | Positive n (%; 95% CI)§ | Contaminated n (%; 95% CI)§ | |
| Spot sputum | 65 (77.6; 72.7–82.5) | 19 (22.4; 17.5–27.32) | 65 (74.8; 72.3–77.5) | 22 (25.2; 22.5–27.8) | 36 (43.0; 35.8–50.1) | 48 (57.0; 49.9–64.2) | 16 (18.3; 13.4–23.2) | 65 (74.6; 69.3–79.9) | 6 (7.1; 3.7–10.4) |
| Morning sputum | 59 (69.5; 62.8–76.3) | 26 (30.5; 23.7–37.2) | 54 (63.7; 55.3–72.2) | 31 (36.3; 27.8–44.7) | 26 (34.0; 27.9–40.1) | 50 (66.0; 59.9–72.1) | 17 (20.0; 14.4–25.7) | 59 (69.2; 61.4–77.0) | 9 (10.7; 5.2–16.2) |
| Lymph node aspirate | n/a | n/a | n/a | n/a | n/a | n/a | 0 | 5 (100, 100–100) | 0 |
| Stool | n/a | n/a | 28 (84.8; 79.2–90.5) | 5 (15.2; 9.5–20.8) | n/a | n/a | 11 (33.3; 16.2–50.5) | 11 (33.3; 9.5–57.1) | 11 (33.3; 16.2–50.5) |
* Of the 88 persons with TB, 84 submitted a spot sputum for ZN microscopy and Xpert MTB/RIF, 87 submitted a spot sputum for fluorescence microscopy and liquid culture, and 85 submitted a morning sputum for all tests; 9 of the morning specimens that were submitted by TB cases were not tested by Xpert MTB/RIF because of limited volume.
† ZN = Ziehl-Neelsen microscopy; FM = Fluorescent Microscopy; Xpert MTB/RIF = GeneXpert MTB/RIF assay; MGIT = Mycobacterial Growth Indicator Tube
‡ Negative MGIT also includes non-tuberculous mycobacteria, which was identified on one spot 1 specimen.
§ Percentages are weighted, and do not equal the proportion based on unweighted counts; 95% CI = 95% confidence interval