| Patients screened | N | T Spot TB (Elispot) result | Chest radiography result | ||
| Non- reactive | Reactive | Indeterminate | Normal/abnormal | ||
| Anti-TNF naïve | 24 | 22 | 1 | 1 | |
| On immunosuppression | (16) | (15) | (0) | (1) | 24/0 |
| No immunosuppression | (8) | (7) | (1) | (0) | |
| Established on anti-TNF | 26 | 24 | 1 | 1 | |
| On immunosuppression | (24) | (22) | (1) | (1) | 26/0 |
| No immunosuppression | (2) | (2) | (0) | (0) | |
TNF, tumour necrosis factor.