How is jra (juvenile arthritis) diagnosed in a teen?

See below. A lot of the diagnosis will be based on the history of joint swelling, redness, and pain. And a physical exam that reveals the joint findings. Then, labs can be ordered to help confirm the diagnosis.
JA- teen diagnosis. The diagnosis is made when there has been arthritis in the joints for greater than 6 weeks. Children may have normal blood work such as a normal ANA test and a normal rheumatoid factor test. The diagnosis is made based on the physical exam and not based on blood work.