Table 1. Characteristics of 261 HIV-infected pulmonary tuberculosis suspects in Mbarara, Uganda by M. tuberculosis culture and TOP TB assay results.
| Characteristic | Overall | Culture positive | Culture negative | P value | ||
|---|---|---|---|---|---|---|
| TOP positive | TOP positive | TOP negative | Overall1 | Two-way2 | ||
| N | 261 | 48 | 139 | 74 | ||
| Age (years) | 39.0 [30.5–47.0] | 33.5 [28.0–40.0] | 42.0 [33.0–49.0] | 38.5 [31.0–48.8] | 0.002 | <0.001 |
| Female sex | 138 (53) | 12 (25) | 78 (56) | 48 (65) | <0.001 | <0.001 |
| Previous TB treatment* | 33 (13) | 3 (6) | 23 (17) | 7 (9) | 0.04+ | 0.05+ |
| Years since previous TB treatment | 9.3 [5.9–10.9] | 5.4 | 9.3 [5.9–10.9] | 11.9 [10.3–12.0] | 0.28# | 0.16# |
| N = 13 | N = 1 | N = 9 | N = 3 | |||
| CD4 (cells/mL)* | 322 [104–495] | 182 [54–338] | 343.5 [93–457] | 355 [158–590] | 0.06 | 0.13 |
| N = 172 | N = 22 | N = 92 | N = 58 | |||
| Sputum volume (mL) | 3 [2–5] | 4 [3–5] | 3 [2–4.5] | 3 [2–5] | 0.33# | 0.16# |
| Sputum appearance^ | <0.001+ | 0.05+ | ||||
| Purulent | 69 (27) | 20 (42) | 36 (26) | 13 (18) | ||
| Mucoid | 36 (13) | 10 (25) | 23 (17) | 3 (4) | ||
| Salivary | 156 (60) | 18 (33) | 80 (58) | 58 (78) | ||
| Chest radiograph* | 0.04+ | 0.05+ | ||||
| Normal | 29/103 (28) | 2/17 (12) | 14/47 (30) | 13/39 (33) | ||
| Minimal | 17/103 (17) | 1/17 (6) | 8/47 (17) | 8/39 (21) | ||
| Moderate | 46/103 (45) | 8/17 (47) | 21/47 (45) | 17/39 (44) | ||
| Far advanced | 11/103 (11) | 6/17 (35) | 4/47 (9) | 1/39 (3) | ||
| Cavitation present | 18/104 (17) | 5/17 (29) | 7/48 (15) | 6/39 (15) | 0.37+ | 0.27+ |
| Sputum AFB smear* | − | <0.001+ | ||||
| Negative | 222 (85) | 11 (23) | 137 (99) | 74 (100) | ||
| Scanty | 9 (3) | 8 (17) | 1 (1) | 0 (0) | ||
| 1+ | 10 (4) | 10 (21) | 0 (0) | 0 (0) | ||
| 2+ | 7 (3) | 6 (13) | 1 (1) | 0 (0) | ||
| 3+ | 13 (5) | 13 (27) | 0 (0) | 0 (0) | ||
| Sputum MGIT culture | ||||||
| Positive | 48 (18) | 48 (100) | 0/139 (0) | 0/74 (0) | - | - |
| Contaminated | 12 (5) | − | 2/139 (1) | 10/74 (14) | ||
| MGIT DTP (days) | 19 [13–33] | 19 [13–33] | NA | NA | - | |
| Xpert Mtb/RIF * | ||||||
| Positive | 50/259 (19) | 45/47 (96) | 3/139 (2) | 2/73 (3) | <0.001+ | <0.001+ |
| Indeterminate | 4/259 (2) | 1/47 (2) | 1/139 (1) | 2/73 (3) | ||
| M. tuberculosis 2-ponA genotype | ||||||
| 0T | 5 (2) | 4 (8) | 1 (1) | 0 | - | 0.005+ |
| 1T | 6 (2) | 3 (6) | 3 (2) | 0 | ||
| 1 | 2 (1) | 0 | 2 (1) | 0 | ||
| 2 | 40 (15) | 16 (33) | 24 (17) | 0 | ||
| 3 | 93 (36) | 18 (38) | 74 (53) | 1 (1) | ||
| 4 | 27 (10) | 3 (6) | 24 (17) | 0 | ||
| Neg | 88 (34) | 4 (8) | 11 (8) | 73 (99) | ||
Values are median [interquartile range] or number (percentage), unless otherwise specified
MGIT = Mycobacterial Growth Indicator Index (BACTEC 960, Becton Dickinson, U.S.A.); DTP = Days-to-positive; AFB = Acid-fast bacilli
1 P overall = Comparison between three groups
2 P two-way = Comparison between culture-positive/ TOP-positive vs. culture-negative/ TOP-positive
* Missing information: Previous TB treatment (1); CD4 cell count (85); Time since previous TB treatment (20); Chest X-ray extent of disease (154), cavitation (153); Sputum AFB smear (1); Xpert MTB/RIF (2)
^ Purulent sputum category includes purulent and muco-purulent; Mucoid category includes mucoid and muco-salivary
+ Fisher’s exact test.
# Kruskal-Wallis test or Wilcoxon test.