Baseline demographic and disease characteristics of patients enrolled in the study. Data are n (%) unless otherwise indicated.
| QFT-GIT | TST | |||||
|---|---|---|---|---|---|---|
| Characteristics | All, n = 102 | Positive, n = 2 | Negative, n = 82 | Indeterminate, n = 18 | Positive, n = 10 | Negative, n = 92 |
| Women | 67 (65.7) | 2 (2.9) | 51 (76.1) | 14 (20.8) | 7 (10.4) | 60 (89.5) |
| Age, yrs, median (range) | 47 (20–82) | 33 (20–46) | 47 (24–82) | 47 (23–65) | 62 (29–74) | 46 (20–82) |
| Underlying disease | ||||||
| Rheumatoid arthritis | 54 (52.9) | 2 (3.7) | 39 (72.2) | 13 (24.1) | 7 (12.9) | 47 (87) |
| Psoriatic arthritis | 34 (33.3) | 0 | 33 (97) | 1 (2.9) | 2 (5.8) | 32 (94.1) |
| Ankylosing spondylitis | 10 (9.8) | 0 | 8 (80) | 2 (20) | 1 (10) | 9 (90) |
| Behçet’s disease | 4 (3.9) | 0 | 2 (50) | 2 (50) | 0 | 4 (100) |
| BCG-vaccinated | 5 (4.9) | 0 | 4 (80) | 1 (20) | 1 (20) | 4 (80) |
| Risk factors for LTBI | ||||||
| Birth or prolonged residence in a TB-endemic area* | 12 (11.7) | 1 (8.3) | 8 (66.6) | 3 (25) | 2 (16.6) | 10 (83.3) |
| History of household contact | 4 (3.9) | 0 | 2 (50) | 2 (50) | 0 | 4 (100) |
| Chest radiograph suggestive of LTBI | 5 (4.9) | 1 (20) | 4 (80) | 0 | 2 (40) | 3 (60) |
| Previous diagnosis of TB | 0 | — | — | — | — | — |
| Concomitant treatment regimen | ||||||
| Glucocorticoids | 10 (9.8) | 0 | 9 (90) | 1 (10) | 1 (10) | 9 (90) |
| DMARD | 19 (18.6) | 2 (10.5) | 16 (84.2) | 1 (5.3) | 1 (5.3) | 18 (94.7) |
| DMARD and glucocorticoids | 55 (53.9) | 0 | 42 (76.4) | 13 (23.6) | 5 (9.1) | 50 (90.9) |
| No immunosuppressants | 18 (17.6) | 0 | 15 (83.3) | 3 (16.6) | 3 (16.6) | 15 (83.3) |
| Dose of immunosuppressants, mg; median/range† | ||||||
| Glucocorticoids†† | 5 (0–50) | — | 5 (0–50) | 6.75 (0–25) | 5 (0–25) | 5 (0–50) |
| Methotrexate | 0 (0–25) | 8.75 (7.5–10) | 7.5 (0–25) | 0 (0–15) | 12.5 (0–20) | 0 (0–25) |
| Leflunomide | 0 (0–20) | — | 0 (0–20) | 0 (0–20) | — | 0 (0–20) |
| Cyclosporine | 0 (0–250) | — | 0 (0–200) | 0 (0–250) | — | 0 (0–250) |
| Sulfasalazine | 0 (0–3000) | — | 0 (0–3000) | 0 (0–3000) | 0 (0–2000) | 0 (0–3000) |
| Azathioprine | 0 (0–100) | — | 0 (0–100) | 0 (0–100) | — | 0 (0–100) |
| Hydroxychloroquine | 0 (0–400) | 200 (0–400) | 0 (0–400) | 0 (0–400) | 0 (0–400) | 0 (0–400) |
↵* Includes Romania (5); Albania, Peru (2 each); Brazil, Argentina, Morocco (1 each).
↵† Daily for all immunosuppressants listed except methotrexate (weekly).
↵†† Prednisone equivalent. TST: tuberculin skin test; QFT-GIT: QuantiFeron-TB Gold In-Tube; BCG: bacille Calmette-Guérin; LTBI: latent tuberculosis infection; TB: tuberculosis; DMARD: disease-modifying antirheumatic drugs [includes methotrexate (50), leflunomide (9), cyclosporine (5), sulfasalazine (22), azathioprine (5), hydroxychloroquine (12)].