Juvenile arthritis is a disease in which there is inflammation (swelling) of the synovium in children aged 16 or younger. The synovium is the tissue that lines the inside of joints. Juvenile arthritis is an autoimmune disease. That means the immune system, which normally protects the body from foreign substances, attacks the body instead. The disease is also idiopathic, which means that no exact cause is known. Researchers believe juvenile arthritis may be related to genetics, certain infections, and environmental triggers.

What are the different types of juvenile arthritis?

There are five types of juvenile arthritis:

1. Systemic arthritis, also called Still’s disease, can affect the entire body or involve many systems of the body. Systemic juvenile arthritis usually causes high fever and a rash. The rash is usually on the trunk, arms, and legs
2. Oligoarthritis, also called pauciarticular juvenile rheumatoid arthritis, affects fewer than five joints in the first six months that the child has the disease. The joints most commonly affected are the knee, ankle, and wrist.
3. Polyarthritis, also called polyarticular juvenile idiopathic arthritis (pJIA), involves five or more joints in the first six months of the disease — often the same joints on each side of the body
4. Psoriatic arthritis affects children who have both arthritis and the skin disorder psoriasis. The child might get either the psoriasis or the arthritis years before developing the other part of the disease.
5. Enthesitis-related arthritis is a type of arthritis that often afflicts the spine, hips, eyes, and entheses (the places where tendons attach to bones). This type of arthritis occurs mainly in boys older than 8 years of age.

What are the symptoms of juvenile arthritis?

• Joint stiffness, especially in the morning
• Pain, swelling, and tenderness in the joints
• Limping (In younger children, it may appear that the child is not able to perform motor skills he or she recently learned.)
• Persistent fever
• Rash
• Weight loss
• Fatigue
• Irritability
• Eye redness or eye pain
• Blurred vision

In general, though, treatment for juvenile arthritis has several main goals:

• To relieve pain
• To reduce swelling
• To increase joint mobility and strength
• To prevent joint damage and complications