Table 5.
Clinical and microbiological factors associated with clustering
| Clustering*
|
Unadjusted
|
Adjusted
|
||||
|---|---|---|---|---|---|---|
| Yes (n = 23) | No (n = 151) | |||||
| n (%) | n (%) | OR (95%CI) | P value | OR (95%CI) | P value | |
| Age ≥65 years† | 2 (8.7) | 9 (6.0) | 1.56 (0.15–8.37) | 0.846 | ||
| Male sex | 11 (47.8) | 79 (52.3) | 0.79 (0.33–1.90) | 0.598 | ||
| Asian race | 11 (47.8) | 95 (62.9) | 0.54 (0.22–1.31) | 0.171 | ||
| Hispanic ethnicity | 12 (52.2) | 43 (28.5) | 2.72 (1.11–6.62) | 0.028 | 26.50 (3.73–386.80) | <0.001 |
| Previous anti-tuberculosis treatment | 3 (13.0) | 43 (28.5) | 0.46 (0.13–1.67) | 0.239 | ||
| HIV infection | 0 | 5 (3.3) | — | — | ||
| Diabetes mellitus† | 3 (13.0) | 4 (2.6) | 5.54 (0.76–35.40) | 0.095 | 3.64 (0.35–35.30) | 0.355 |
| BCG vaccination† | 1 (4.3) | 32 (21.2) | 0.17 (0.004–1.17) | 0.087 | 0.18 (0.004–1.39) | 0.140 |
| Homeless in last 12 months† | 2 (8.7) | 5 (3.3) | 2.72 (0.24–18.00) | 0.473 | ||
| Correctional facility at time of diagnosis† | 1 (4.3) | 4 (2.6) | 1.68 (0.03–18.00) | 1.000 | ||
| Long-term care facility at time of diagnosis | 0 | 2 (1.3) | — | — | ||
| Injecting drug user in last 12 months† | 1 (4.3) | 1 (0.7) | 6.65 (0.08–535.00) | 0.497 | ||
| Excessive alcohol in last 12 months† | 9 (39.1) | 13 (8.6) | 6.61 (2.11–20.50) | <0.001 | ||
| East-Asian lineage infection | 15 (65.2) | 55 (36.4) | 3.27 (1.30–8.21) | 0.012 | 30.00 (4.20–462.40) | <0.001 |
| rpoA or rpoC mutations† | ||||||
| No mutations | 19 (82.6) | 120 (79.5) | 1.00 | — | ||
| Overall mutations | 4 (17.4) | 31 (20.5) | 0.80 (0.19–2.66) | 0.954 | ||
| rpoC mutation | 4 (17.4) | 27 (17.9) | 0.95 (0.22–3.17) | 1.000 | ||
| rpoA mutation | 0 | 4 (2.7) | — | — | ||
| rpoB mutation status | ||||||
| Without S531L mutation | 6 (26.1) | 63 (41.7) | 1.00 | — | ||
| With S531L mutation | 17 (73.9) | 88 (58.3) | 2.03 (0.76–5.43) | 0.159 | 4.03 (1.05–23.10) | 0.040 |
| katG mutation status | ||||||
| Without katG mutation | 4 (17.4) | 46 (30.5) | 1.00 | — | ||
| With katG mutation | 19 (82.6) | 105 (69.5) | 2.08 (0.67–6.46) | 0.205 | ||
*
Defined as isolates collected in the same state and sharing identical spoligotyping, 24-locus mycobacterial interspersed repetitive units typing, insertion sequence 6110 restriction fragment length polymorphism pattern and drug-resistance-associated mutations.
†
As expected cell counts were <5, unadjusted ORs and P values were calculated using the exact logistic method.
OR = odds ratio; CI = confidence interval; HIV = human immunodeficiency virus; BCG = bacille Calmette-Guérin.