More to Know

Causes of JIA are not known ("idiopathic" is a medical term used to describe a disease with no known cause). But experts believe it's an autoimmune disease (when the body's immune system isn't working correctly).

There are seven major types of JIA, and they usually affect kids and teens between 6 months and 16 years old. The first signs can include limping or a sore wrist, finger, or knee. Joints may suddenly swell and remain enlarged. Stiffness in the neck, hips, or other joints also can occur.

JIA is a chronic condition, meaning it can last for months and years. Sometimes the symptoms go away on their own (called remission). Remission may last for months, years, or a person's lifetime.

Keep in Mind

An early and accurate diagnosis is key to effectively managing JIA. Understanding the symptoms and characteristics of each type of JIA can help a person maintain an active, productive lifestyle.

Medications might be used for pain and inflammation or to aid the immune system, and physical therapy and exercise sometimes help. Rarely, a person might need surgery or corticosteroid injections.

All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.