A term referring to a variety of conditions characterized by inflammation of one or more joints.

Arthritis is commonly regarded as a disease of the elderly, but there are several varieties that primarily affect children, including juvenile rheumatoid arthritis, infectious arthritis, and juvenile ankylosing spondylitis.

Juvenile Rheumatoid Arthritis (Jra)

The most common form of arthritis in children is juvenile rheumatoid arthritis, also known as JRA or Still's disease. Affecting over 65,000 young people in the United States—roughly 1 in 1,000—it can affect children as young as two years old. The condition occurs in "flareups" that can last from a few weeks to several years, alternating with periods of remission. JRA, like other types of arthritis, is thought to be an autoimmune disease, in which antibodies that are supposed to protect the body from foreign invaders turn against its own tissues, primarily the joints. The synovium, a thin membrane surrounding...