Extended oligoarthritis
Extended oligoarthritis is a type of juvenile idiopathic arthritis (JIA). This form of JIA starts as oligoarthritis in the first 6 months, which is usually a mild form of arthritis, and then causes problems with many joints (5 or more) after that.
This type of JIA can cause damage to your joints and your doctor may suggest early treatment with drugs like methotrexate to keep this damage to a minimum.
Read more about JIA.