Early onset sarcoidosis masquerading as juvenile rheumatoid arthritis.

Symptoms of early onset sarcoidosis characterized by skin eruptions, arthritis, and uveitis mimic those of systemic type juvenile rheumatoid arthritis (JRA). We report 2 Japanese patients with early onset sarcoidosis, both of whom were initially diagnosed and treated as having JRA. Intermittent fever and synovial swelling may mask sarcoidosis in children less than 4 years old.