According to the Arthritis Foundation, that means nearly 3 of every 1,000 children are living with a form of arthritis. The most common form of the disease among children is juvenile rheumatoid arthritis. Characterized by inflammation of the membrane lining the joint, JRA invades the synovium, the joint lining, and damages bone and cartilage by releasing enzymes that digest the bone and cartilage. JRA may affect growth during active periods of the disease. Onset occurs between the ages of 2 to 5 years of age and 9 to 12 years of age.
Girls are also at a higher risk than boys.
The specific cause of JRA is still being researched, however, medical experts know JRA is an autoimmune disease. The body's immune system begins to attack healthy joint tissue because it cannot recognize good tissue from bad tissue. This results in inflammation and joint damage. Researchers believe JRA may occur in children who have inherited a genetic marker called HLA-DR4. With increased education, children will not have to suffer the pains of an illness that shouldn't keep them from enjoying life.