Related Experiment Video
Updated: Feb 18, 2026
An Adoptive Transfer Model of Rheumatoid Arthritis in Mice
Published on: June 6, 2025
Patients with very early-onset systemic juvenile idiopathic arthritis exhibit more inflammatory features and a worse
Ricardo A G Russo1, María M Katsicas
1Service of Immunology and Rheumatology, Hospital de Pediatría Prof. Dr. Juan P. Garrahan, Buenos Aires, Argentina. rrusso@garrahan.gov.ar
Insights
Early-onset systemic juvenile idiopathic arthritis (SJIA) leads to more aggressive disease and greater joint damage. This finding highlights the need for early intervention in young children diagnosed with SJIA.
Area of Science:
- Pediatric Rheumatology
- Immunology
- Clinical Medicine
Background:
- Systemic juvenile idiopathic arthritis (SJIA) is a severe autoimmune condition causing joint damage and disability.
- Early identification of predictive factors for poor outcomes in SJIA is crucial for timely intervention.
- Younger age at onset and persistent systemic features are associated with worse SJIA prognosis.
Purpose of the Study:
- To analyze disease characteristics and outcomes in patients with early-onset SJIA (onset before 18 months).
- To compare the clinical presentation and long-term outcomes of early-onset SJIA with later-onset SJIA.
- To identify specific features associated with a more aggressive disease course in young SJIA patients.
Main Methods:
- Retrospective analysis of clinical data from 132 SJIA patients followed for at least 3 years.
- Comparison of disease features at onset between early-onset (EO) and later-onset (LO) SJIA groups.
- Assessment of outcomes including macrophage activation syndrome, remission, disability (CHAQ), and joint damage (JADI).
Main Results:
- Early-onset SJIA (n=19) presented with more frequent serositis and hepatomegaly, lower hemoglobin, and higher platelets compared to LO SJIA (n=113).
- Macrophage activation syndrome occurred more frequently in EO patients (p < 0.0001).
- EO patients experienced significantly higher rates of hip destruction, growth retardation, radiographic damage, and disability, with higher JADI scores.
Conclusions:
- Early-onset SJIA is associated with a more aggressive and destructive disease phenotype.
- Patients with early-onset SJIA demonstrate poorer long-term outcomes regarding joint damage and functional disability.
- These findings underscore the importance of recognizing and managing early-onset SJIA aggressively.
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.
Related Concept Videos
01:22Rheumatic Heart Disease II: Clinical Manifestations and Diagnostic Studies
01:30Inflammatory Bowel Disease II: Crohn's Disease
Inflammatory bowel disease, commonly known as IBD, refers to a collection of disorders that lead to persistent inflammation of the gastrointestinal tract. The two types of IBD are ulcerative colitis, which impacts the colon, and Crohn's disease, which can involve any part of the gastrointestinal segment.
Crohn's disease
Crohn's disease is a chronic, systemic inflammatory bowel disease (IBD) that predominantly affects the gastrointestinal tract. It is marked by...
01:28Inflammatory Response
Inflammation can be triggered by various stimuli, such as impact, abrasion, chemical irritation, infections, and extreme hot or cold temperatures. These can damage cells and connective tissue fibers,...
01:20The JAK-STAT Signaling Pathway
01:29Autoimmune Disorders
Concept and Mechanism of Autoimmune Diseases
The immune...
01:20COPD: Pathogenesis and Clinical Features
The primary cause for the onset of COPD is cigarette smoking and exposure to air pollution. These hazardous factors initiate a chain reaction within the lungs, resulting in chronic inflammation, damage to the airways, and a...