Table 1.
Baseline demographics and clinical characteristics of the three groups of patients at the time of blood collection for multi-functional analysis of T cells.
| Characteristics | Group A (n = 12) |
Group B (n = 11) |
Group C (n = 10) |
|---|---|---|---|
| M/F (n) | 5/7 | 7/4 | 4/6 |
| Age (years; median/range) | 63·5/21–76 | 45/36–71 | 58/30–75 |
| Underlying disease (n/%) | |||
| Rheumatoid arthritis | 9/75 | 2/18·2 | 4/40 |
| Psoriatic arthritis | 1/8·3 | 6/54·5 | 5/50 |
| Ankylosing spondylitis | 2/16·7 | 3/27·3 | 1/10 |
| BCG-vaccinated (n/%) | 0 | 0 | 0 |
| Risk factors for LTBI (n/%) | |||
| Birth in a TB-endemic area† | 1/8·3 | 0 | 1/10 |
| History of household contact | 0 | 1/9·1 | 0 |
| Chest X-ray suggestive of LTBI | 4/33·3 | 0 | 0 |
| Previous diagnosis of TB | 0 | 0 | 0 |
| Concomitant treatment regimen (n/%) | |||
| Glucocorticoids | 0 | 0 | 0 |
| DMARDs | 0 | 0 | 0 |
| Biologicals | 3/25 | 8/72·7 | 4/40 |
| DMARDs + glucocorticoids | 3/25 | 0 | 0 |
| Biologicals + glucocorticoids | 1/8·3 | 1/9·1 | 1/10 |
| Biologicals + DMARDs | 2/16·7 | 1/9·1 | 3/30 |
| Biologicals + DMARDs + glucocorticoids | 1/8·3 | 0 | 2/20 |
| No immunosuppressants | 2/16·7 | 1/9·1 | 0 |
Includes Albania (group A) and Argentina (group C). Group A: patients with latent tuberculosis infection (LTBI) (before the onset of biological therapy) showing fluctuations (conversions/reversions) in released interferon (IFN)-γ levels in the QuantiFERON-TB Gold In-Tube (QFT-GIT) during long-term treatment with biological agents. Group B: patients with no evidence of LTBI at baseline showing IFN-γ levels fluctuations during follow-up. Group C: patients with no evidence of LTBI at baseline showing persistently negative IFN-γ levels released in the QFT-GIT during follow-up. BCG = bacille Calmette-Guérin; DMARDs = disease modifying anti-rheumatic drugs; TB = tuberculosis; M/F = male/female. DMARDs include methotrexate, leflunomide, cyclosporin A, sulphasalazine, azathioprine and hydroxychloroquine.