Diagnosis

diagnosis

Diagnosis of JIA is made through history and physical examination.

• no conclusive laboratory tests are available for the diagnosis
• it is important to exclude other joint problems with a discernable cause

In history inquire about:

• joint pain and swelling and also about similar symptoms prior to this episode
• morning stiffness that lasts for more than 15 minutes but improves during the day
• autoimmune disease in relatives
• specific family history - in suspected psoriatic arthritis and enthesitis related arthritis
• any systemic features e.g. - rash or intermittent pyrexia
• any problems with walking, running, climbing stairs, standing up, writing, or sleeping - specially from parents, other family members, or teachers
• any assistance given to carry out daily activities that were previously performed independently

Physical examination should include:

• examination of all joints for
  • pain or tenderness
  • swelling
  • redness
  • limited movement
  • decreased strength or muscle atrophy
  • bony deformity
• child should be observed while walking, standing up, sitting down, or climbing on to the examination table
• general examination
  • lymphadenopathy
  • organ enlargement
  • systemic rashes
  • nail abnormalities
  • psoriatic rash, or enthesitis
• growth measurements
• eye examination by ophthalmologists for uveitis

Further investigations which can be carried out for all subtypes include:

• full blood count
• inflammatory markers -erythrocyte sedimentation rate, C reactive protein
• autoimmune markers - rheumatoid factor, HLA B27, and antinuclear antibodies
• imaging studies
  • radiography - narrowing of the joint spaces or erosions, maturation differences or growth abnormalities in bones from an early stage
  • MRI - inflamed synovium and increased joint fluid

Reference:

• (1) Prince FH, Otten MH, van Suijlekom-Smit LW. Diagnosis and management of juvenile idiopathic arthritis. BMJ. 2010;341:c6434