children s health issues
Juvenile Idiopathic Arthritis (JIA)
Diagnosis of JIA
A doctor's evaluation Blood tests A doctor diagnoses JIA based on the child's symptoms and the results of a physical examination. There is no single, definitive laboratory test for JIA, but some blood tests are helpful in distinguishing one form from another. Blood is tested for a full blood count, rheumatoid factor, antinuclear antibodies, anti-cyclic citrullinated peptide antibodies, and a certain antigen called HLA-B27, some of which are present in some people with rheumatoid arthritis and related autoimmune diseases. The results of these tests can help doctors distinguish one form of JIA from another. However, most children with JIA do not have rheumatoid factor and most do not have antinuclear antibodies in their blood. Other blood tests, such as ferritin, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR), might also be done. Increased levels of CRP and ESR indicate inflammation. Children with JIA who have antinuclear antibodies in their blood are at a higher risk of developing iridocyclitis. Children must be examined several times a year by an eye specialist (an ophthalmologist) for iridocyclitis regardless of whether symptoms are present because iridocyclitis may not cause any symptoms even though it is already causing eye inflammation. Children who have oligoarticular JIA or polyarticular JIA and who have antinuclear antibodies in their blood should have an eye examination every 3 months. Children who have oligoarticular or polyarticular JIA but who do not have antinuclear antibodies in their blood should have an eye examination every 6 months. Children who have systemic JIA should have an eye examination once a year. X-rays may be taken to look for characteristic changes in the bones or joints. 