Arthritis, Juvenile Chronic

Rheumatoid Arthritis of Children occurring in three major subtypes defined by the symptoms present during the first six months following onset: systemic-onset (Still's Disease, Juvenile-Onset), polyarticular-onset, and pauciarticular-onset. Adult-onset cases of Still's Disease (Still's Disease, Adult-Onset) are also known. Only one subtype of juvenile Rheumatoid Arthritis (polyarticular-onset, Rheumatoid Factor-positive) clinically resembles Adult Rheumatoid Arthritis and is considered its childhood equivalent.