There used to be two ways to classify juvenile
arthritis. There was the European classification of juvenile chronic arthritis (JCA). And there was the American classification of
juvenile rheumatoid arthritis (JRA). Each system used different categories. This made it hard to use European and American
research findings and treatment guidelines together.
improve research and treatment, the International League Against Rheumatism has
devised a set of international criteria that uses the term "juvenile
idiopathic arthritis" (JIA). The word "idiopathic" means "of unknown cause." This approach is
now used by most researchers and health professionals.
The table below summarizes the three
Classification systems for juvenile arthritis
Length of illness before diagnosis
International League Against
Juvenile idiopathic arthritis (JIA)
Persistent. It affects 1 to 4
Extended. Over time it affects 5 or more joints.
arthritis (This is also called undifferentiated or unclassified arthritis.)
American College of Rheumatology
Juvenile rheumatoid arthritis (JRA)
JRA. It affects 5 or more joints.
Oligoarticular JRA. It affects 1 to 4 joints.
JRA does not include similar types of childhood
arthritis (juvenile ankylosing spondylitis, juvenile psoriatic
European League Against Rheumatism
Juvenile chronic arthritis (JCA)
JCA. It affects 5 or more joints and is RF-negative.
Juvenile rheumatoid arthritis. It affects 5 or more joints and is RF-positive.
Oligoarticular JCA. It affects 1 to 4
Juvenile psoriatic arthritis
No matter the classification, children who have
symptoms before age16 are said to have juvenile