Comparison of characteristics in patients on immunosuppressants classified according to risk stratification, tuberculin skin test (TST) positivity and T.Spot positivity
| High risk according to BTS n=27 | Low risk according to BTS n=110 | p Value | TST positive n=31 | TST negative n=106 | p Value | T.Spot positive n=25 | T.Spot negative n=111* | p Value | |
|---|---|---|---|---|---|---|---|---|---|
| Male sex (%) | 15 (55.6) | 45 (40.9) | 0.197 | 18 (58.1) | 42 (39.6) | 0.099 | 14 (56.0) | 46 (41.4) | 0.265 |
| Age | 50 (44–60) | 57 (45–68) | 0.063 | 57 (49–68) | 55 (44–65) | 0.530 | 56 (46–68) | 55.5 (44–66) | 0.624 |
| Ethnicity | |||||||||
| Caucasian (%) | 0 (0) | 83 (75.5) | <0.001 | 19 (61.3) | 64 (60.4) | 1.0 | 16 (64.0) | 67 (60.4) | 0.823 |
| Black African (%) | 8 (29.6) | 0 (0) | <0.001 | 2 (6.5) | 6 (5.7) | 1.0 | 3 (12.0) | 5 (4.5) | 0.163 |
| Asian (%) | 15 (55.6) | 0 (0) | <0.001 | 3 (9.7) | 12 (11.3) | 1.0 | 1 (4.0) | 14 (12.6) | 0.304 |
| Other (%) | 4 (14.8) | 27 (24.5) | 0.441 | 7 (22.6) | 24 (22.6) | 1.0 | 5 (20.0) | 25 (22.5) | 1.0 |
| High risk according to BTS (%) | − | − | − | 5 (16.1) | 22 (20.8) | 0.798 | 4 (16.0) | 23 (20.7%) | 0.783 |
| TST positive (%) | 4 (14.8) | 26 (23.6) | 0.439 | − | − | − | 9 (36.0) | 22 (19.8) | 0.112 |
| T.Spot positive (%) | 4 (14.8) | 21 (19.1) | 0.783 | 9 (29.0) | 16 (15.1) | 0.110 | − | − | − |
| Indeterminate T.Spot (%) | 0 (0) | 1 (0.9) | 1.0 | − | − | − | − | − | − |
| T.Spot and TST both positive (%) | 1 (3.7) | 8 (7.3) | 0.688 | − | − | − | − | − | − |
| Either T.Spot and/or TST positive (%) | 7 (25.9) | 39 (35.5) | 0.496 | − | − | − | − | − | − |
*Total=136 due to one patient having indeterminate T.Spot result.
Data presented as median (IQR) or n (%); p values show comparison of proportions between groups or median values for continuous variables.
BTS, British Thoracic Society.