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Start free with EleplanRheumatoid factor-negative polyarticular juvenile idiopathic arthritis
ORPHA:85408Disease
Also called Juvenile polyarthritis without rheumatoid factor · Juvenile rheumatoid factor-negative polyarthritis · Rheumatoid factor-negative polyarticular JIA
What it is
A rare form of polyarticular juvenile idiopathic arthritis characterized by childhood-onset chronic arthritis of unknown cause involving five or more joints at disease onset and absence of rheumatoid factor IgM.
Key facts
- Prevalence
- 1-9 / 100 000 (Europe)
- Age of onset
- Childhood
- Inheritance
- Multigenic/multifactorial
- Classified as
- Disease
Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.
Signs and symptoms
Common30–79%
11These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
Genes
ICD-10 codes
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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