Abstract
OBJECTIVE: To analyze the levels of high mobility group box 1 (HMGB1) protein on different courses of juvenile idiopathic arthritis (JIA). METHODS: In our prospective longitudinal study, children with JIA were included with their blood samples collected at the first visit, 1-month, 3-month, and 6-month follow-up, respectively. Samples were also collected from healthy controls and children with reactive arthritis at the first visit. Levels of HMGB1 were determined using enzyme-linked immunosorbent assays. Clinical disease characteristics and routine laboratory findings were analyzed as well. RESULTS: A total of 64 children were enrolled, of whom 31 (48.4%) were female. The median age at the first visit for participants with JIA was 9.25 years (range, 1.42-15.42) and the median duration of disease was 2.38 months (range, 1.53-49.31). Serum HMGB1 levels at the first visit were significantly elevated in children with systemic JIA compared with other groups, and so were in enthesitis-related arthritis versus healthy controls. Significant correlations were established at the first visit between HMGB1 levels and duration of disease, C-reactive protein, percentage of neutrophils, and ferritin. Data from all samples revealed that serum HMGB1 levels in JIA were significantly associated with erythrocyte sedimentation rates, C-reactive protein, percentage of neutrophils, and disease activity scores. CONCLUSIONS: Serum HMGB1 may be associated with clinical disease activity of JIA and specifically increased at the first visit in children with systemic JIA, suggesting its function as a sensitive inflammatory marker. Further large-scale studies are warranted to explore its spectrum in JIA.