@article {Russojrheum.120386, author = {Ricardo A.G. Russo and Mar{\'\i}a M. Katsicas}, title = {Patients with Very Early-onset Systemic Juvenile Idiopathic Arthritis Exhibit More Inflammatory Features and a Worse Outcome}, elocation-id = {jrheum.120386}, year = {2013}, doi = {10.3899/jrheum.120386}, publisher = {The Journal of Rheumatology}, abstract = {Objective Systemic juvenile idiopathic arthritis (SJIA) frequently leads to disability and damage. Predictive factors for a poor outcome include persistent systemic features and younger age at onset. We describe and analyze disease features in patients with early-onset (EO) SJIA (disease onset before age 18 mo) and compare them to patients with later-onset (LO) disease. Methods Clinical features at onset, activity measures (occurrence of macrophage activation syndrome, remission), and outcome measures for disability [Childhood Health Assessment Questionnaire (CHAQ) >= 0.5] and damage [radiographic joint destruction, Juvenile Arthritis Damage Index (JADI) score, growth retardation] observed during followup were analyzed retrospectively in patients with SJIA followed for >= 3 years since disease onset. Results In total 132 patients were included. SJIA started at age <= 18 months in 19 (14\%) patients and at a later age in 113 (86\%) children. At onset, serositis (p \< 0.01) and hepatomegaly (p \< 0.05) were more frequent in EO patients, who also exhibited lower hemoglobin levels (p \< 0.03) and higher platelet counts (p \< 0.03) than patients with LO. Macrophage activation syndrome occurred in 20 patients (11 EO and 9 LO; p \< 0.0001). Remission was achieved by 49 patients (37\%; 4 EO and 45 LO). At last visit, destructive hip disease (p \< 0.04), growth retardation (p \< 0.01), radiographic damage (p \< 0.02), and disability (p \< 0.04) were more frequent in patients with EO disease, who had higher JADI scores (p \< 0.003). Conclusion Patients with EO exhibited a more aggressive and destructive disease course than patients with LO SJIA.}, issn = {0315-162X}, URL = {https://www.jrheum.org/content/early/2013/01/11/jrheum.120386}, eprint = {https://www.jrheum.org/content/early/2013/01/11/jrheum.120386.full.pdf}, journal = {The Journal of Rheumatology} }