Volume 16, Number 9—September 2010
Research
Determinants of Multidrug-Resistant Tuberculosis Clusters, California, USA, 2004–2007
, Elizabeth Y. Kim, S.-Y. Grace Lin, Adithya Cattamanchi, Peter Oh, Jennifer Flood, Philip C. Hopewell, and Midori Kato-Maeda
Table 1
Demographic and clinical characteristics of 123 patients with clustered and nonclustered MDR TB infections, California, USA, 2004–2007*
| Characteristic | Nonclustered, n = 98† | Clustered, n = 25† | OR‡ (95% CI) | p value |
|---|---|---|---|---|
| Median age, y (IQR) | 39 (30–50) | 27 (18–53) | – | 0.05 |
| Female gender |
47 (48) |
11 (44) |
0.9 (0.3–2.3) |
0.72 |
| Foreign birth | 92 (94) | 21 (84) | 0.3 (0.1–1.8) | 0.11 |
| Nation or region of origin | ||||
| Philippines | 20 (20) | 1 (4) | – | <0.001 |
| Mexico | 16 (16) | 5 (20) | ||
| Vietnam | 14 (14) | 1 (4) | ||
| China | 12 (12) | 0 | ||
| Central America | 6 (6) | 0 | ||
| India | 3 (3) | 3 (12) | ||
| Laos | 2 (2) | 6 (24) | ||
| Thailand | 1 (1) | 4 (16) | ||
| United States | 6 (6) | 4 (16) | ||
| All other nations§ | 18 (18) | 1 (4) | ||
| Recent immigration from refugee setting |
4 (4) |
7 (28) |
9.1 (2–45) |
<0.001 |
| Median time from US entry to diagnosis, y (IQR) | 2.4 (0.2–8.7) | 4.2 (0.2–11) | – | 0.77 |
| Time from US entry to MDR diagnosis¶ | ||||
| <3 mo | 25 (27) | 6 (29) | – | 0.42 |
| 3 mo–3 y | 25 (27) | 4 (19) | ||
| >3 y |
40 (44) |
11 (52) |
||
| Known HIV/TB co-infection |
3 (6) |
0 |
– |
– |
| Private healthcare provider | 11 (11) | 4 (16) | 1.3 (0.3–5.4) | 0.74 |
| Homelessness |
6 (6) |
1 (4) |
0.7 (0.01–5.9) |
1.0 |
| Previous active TB | 28 (29) | 7 (28) | 1.0 (0.3–2.9) | 1.0 |
| Sputum-positive AFB smear |
60 (66) |
16 (70) |
1.2 (0.4–3.8) |
0.81 |
| Extrapulmonary disease# | 7 (7) | 1 (4) | 0.6 (0.1–3.9) | 1.0 |
| Cavitary disease |
25 (26) |
10 (42) |
1.9 (0.7–5.8) |
0.22 |
| Median time to culture conversion, mo (IQR) | 2.2 (1.3–4.6) | 3 (1.4–4.4) | 0.57 | |
| Median total treatment time, mo (IQR) |
25.8 (21.4–28.9) |
24.4 (22.6–27.3) |
0.56 |
|
| Treatment failure** | 4 (7) | 1 (6) | 0.9 (0.02–9.7) | 0.56 |
| Treatment outcome†† | 0.70 | |||
| Completed treatment | 70 (83) | 17 (81) | ||
| Moved | 7 (8) | 1 (5) | ||
| Defaulted | 2 (2) | 0 | ||
| Died | 5 (6) | 3 (14) |
*MDR TB, multidrug-resistant tuberculosis; OR, odds ratios; CI, confidence interval; IQR, interquartile range; AFB, acid-fast bacilli. – indicates OR had no meaning for those specific comparisons.
†Values are no. (%) except as indicated.
‡ORs describe the association between the characteristic of interest and MDR TB case-clustered status. The denominator for each characteristic excludes missing or unknown values.
§Afghanistan (1), Burma (1), Cambodia (5), Ethiopia (1), Indonesia (1), Mongolia (1), Nepal (1), Peru (2), South Korea (5), and Ukraine (1).
¶Date of US entry was missing for 2 persons.
#Nonclustered cases: cervical lymph node (5), bone (1), other (1); clustered cases: pleural (1).
**Culture positive after >8 months of treatment; limited to pulmonary TB patients who were alive at diagnosis and had an initial positive sputum culture.
††Treatment outcome available for 105 (85%) cases.