Initial clinical characteristics of children with SA, JIA and arthritis with no definitive diagnosis
| According to group | Total | ||||
|---|---|---|---|---|---|
| Variable | Group 1: SA (n=63) | Group 2: No definitive diagnosis* (n=45) | Group 3: JIA (n=17) | p Value | n=125 |
| Age at diagnosis (years) | |||||
| Median (IQR) | 1.5 (1.2–3.0) | 3.1 (1.7–5.5) | 3.6 (2.2–5.6) | <0.001 | 2.2 (1.3–4.1) |
| Min–Max | 0.8–13.7 | 0.3–14.6 | 1.5–12.2 | 0.3–14.6 | |
| Male, % (n) | 50.8 (32) | 55.6 (25) | 47.1 (8) | 0.83 | 52.0 (65) |
| Onset in autumn or winter, % (n) | 49.2 (31) | 33.3 (15) | 56.3 (9) | 0.15 | 44.4 (55) |
| Number of affected joints, % (n) | |||||
| Monarthritis | 100 (63) | 91.1 (41) | 82.4 (14) | <0.01 | 94.4 (118) |
| Oligoarthritis (2–4 joints) | 0 (0) | 8.9 (4) | 17.6 (3) | 5.6 (7) | |
| Polyarthritis (≥5 joints) | 0 | 0 | 0 | 0 | |
| Affected joints, % (n) | |||||
| Knee | 57.2 (36) | 37.8 (17) | 64.7 (11) | 0.30 | 51.2 (64) |
| Hip | 23.8 (15) | 44.4 (20) | 23.5 (4) | 31.2 (39) | |
| Ankle | 9.5 (6) | 6.7 (3) | 5.9 (1) | 8.0 (10) | |
| Other joints | 9.5 (6) | 11.1 (5) | 5.9 (1) | 9.6 (12) | |
| Family history of inflammatory disease, % (n) | 3.0 (1) | 8.3 (2) | 26.7 (4) | 0.03 | 9.7 (7) |
| Missing data | N=30 | N=21 | N=2 | N=53 | |
| Duration of fever prior to admission | |||||
| Median (IQR) | 2 (1–3) | 1 (0–3) | 1 (0–7) | 0.44 | 1 (0–4) |
| Min–Max | 0–8 | 0–11 | 0–24 | 0–24 | |
| Duration of local symptoms prior to admission | |||||
| Median (IQR) | 2 (1–4) | 2 (1–4) | 7 (1–19) | 0.04 | 2 (1–5) |
| Min–Max | 1–14 | 1–15 | 1–30 | 1–30 | |
| Duration of symptoms prior to admission (local or fever), | |||||
| Median (IQR) | 3 (1–4) | 3 (1–5) | 7 (2–19) | 0.06 | 3 (1–5) |
| Min–Max | 0–14 | 1–15 | 1–30 | 0–30 | |
| Temperature at admission | |||||
| Median (IQR) | 37.6 (37.0–38.4) | 37.4 (36.9–37.9) | 37.3 (36.7–37.7) | 0.17 | 37.4 (36.9–38.2) |
| Min–Max | 36.0–40.0 | 36.0–39.4 | 36.4–39.3 | 36.0–40.0 | |
| Duration of hospital stay | |||||
| Median (IQR) | 7 (5–8) | 6 (5–7) | 11 (6–12) | 0.05 | 7 (5–8) |
| Min–Max | 1–14† | 1–32 | 2–32 | 1–32 | |
Arthritis with no definitive diagnosis: Arthritis that did not fulfil the criteria for SA, JIA or other well established diagnoses.
†The child with SA and a hospital stay of 1 day was transferred to another hospital.
JIA, juvenile idiopathic arthritis; SA, septic arthritis.