Characteristics of children with and without anti-IFX antibodies. Data are n (%) or means with SD.
| Characteristics | Total, n = 62 (100%) | Anti-IFX AB+, n = 14 (23%) | Anti-IFX AB−, n = 48 (77%) | p |
|---|---|---|---|---|
| Female | 44 (71) | 12 (86) | 32 (67) | 0.170 |
| Patients with (history of) infusion reactions | 10 (16) | 7 (50) | 3 (6) | < 0.001 |
| Age at diagnosis, yrs | 5.7 (3.6) | 4.3 (3.3) | 6.1 (3.7) | 0.100 |
| Diagnosis | ||||
| JIA | 34 (55) | 11 (79) | 23 (48) | 0.060 |
| JIA with associated uveitis | 19 (31) | 3 (21) | 16 (33) | |
| Idiopathic uveitis | 9 (15) | 0 | 9 (19) | |
| Treatment indication | ||||
| Arthritis | 36 (58) | 12 (86) | 24 (50) | 0.036 |
| Uveitis | 15 (24) | 2 (14) | 13 (27) | |
| Arthritis and uveitis | 11 (18) | 0 | 11 (23) | |
| Age at start of IFX treatment, yrs | 9.2 (3.4) | 7.0 (3.5) | 9.9 (3.1) | 0.003 |
| Age at study entry, yrs | 11.3 (3.5) | 9.9 (4.1) | 11.7 (3.2) | 0.138 |
| Disease duration at start of IFX, yrs | 3.5 (3.0) | 2.7 (1.9) | 3.8 (3.2) | 0.933 |
| Duration of IFX, yrs | 3.4 (2.6) | 3.9 (2.9) | 3.3 (2.5) | 0.585 |
| Duration of IFX until first blood sample, yrs | 1.9 (2.3) | 2.2 (2.3) | 1.8 (2.3) | 0.396 |
| Duration of IFX before first infusion reaction, days | 391 (360) | 395 (425) | 384 (200) | 0.969 |
| IFX start dose, mg/kg | 6.0 (1.5) | 5.8 (1.5) | 6.1 (1.5) | 0.359 |
| Systemic corticosteroids | 12 (19) | 0 | 12 (25) | NA |
| Co-medication | ||||
| MTX | 53 (85) | 11 (79) | 42 (88) | 0.312 |
| Leflunomide | 7 (11) | 3 (21) | 4 (8) | |
| Azathioprine | 2 (3) | 0 | 2 (4) | |
| MTX dose, mg/m2/week* | 6.2 (1.8) | 6.5 (2.2) | 6.1 (1.7) | 0.482 |
| Previous biologic treatment | 17 (27) | 4 (29) | 13 (27) | 0.912 |
| Etanercept | 14 (23) | 3 (21) | 11 (23) | |
| Adalimumab | 2 (3) | 1 (7) | 1 (2) | |
| Golimumab | 1 (2) | 0 | 1 (2) |
↵* Mean dose during the study period. AB: antibody; IFX: infliximab; JIA: juvenile idiopathic arthritis; MTX: methotrexate; NA: not applicable.