Table 1. Clinical features and laboratory values of patients with systemic juvenile idiopathic arthritis (sJIA), in sJIA flare, and in patients with macrophage activation syndrome (MAS) complicating sJIA.
| Onset of sJIA n (35) |
Flare of sJIA n (8) |
Systemic JIA with MAS n (6) |
|
|---|---|---|---|
| Fever | 35/35 | 8/8 | 6/6 |
| Arthritis | 35/35 | 6/8 | 1/6 |
| Evanescent rash | 35/35 | 8/8 | 0 |
| Generalized lymphadenopathy | 2/35 | 0 | 0 |
| Hepatomegaly | 8/35 | 4/8 | 5/6 |
| Splenomegaly | 4/35 | 1/8 | 1/6 |
| Serositis | 3/35 | 0 | 1/6 |
| Hemorrhages | 0 | 0 | 1/6 |
| CNS involvement | 0 | 0 | 0 |
| CRP (mg/L) | 132.2 (31.7-320.8) | 59 (25-124) | 123 (65-431.4) |
| ESR (mm/h) | 81 (32-142) | 39 (25-70) | 27.5 (14-55) |
| Hemoglobin (g/dL) | 108 (77-130) | 118 (87-128) | 105 (87-127) |
| WBC (x109/L) | 16.6 (9.6-44.8) | 13.8 (7.6-24.8) | 6.1 (4.0-7.4) |
| Platelets (x109/L) | 436 (275-868) | 322 (204-371) | 177 (124-271) |
| Fibrinogen (g/L) | 6.7 (5.1-8.4) | 5.5 (3.6-6.2) | 3.3 (2.1-4.2) |
| D-dimer (mg/L) | 2.8 (0.8-14.2) | 2.3 (0.33-5.9) | 5.5 (1.4-45.6) |
| Ferritin (µg/L) | 412 (129.9-9843) | 570 (173.7-11229) | 3531(783-20000) |
| AST (U/L) | 28 (15-61) | 42 (15-74) | 66 (26-210) |
| Triglycerides (mmol/L) | 1.30 (0.53-1.87) | 1.29 (1.18-1.90) | 2.09 (1.29-3.92) |
CNS = central nervous system; CRP = C-reactive protein; ESR = erythrocyte sedimentation rate; WBC = white blood cell count; AST = aspartate aminotransferase