Synopsis
Recognise persistent inflammatory arthritis in children, exclude infection and malignancy, classify subtype and institute early rheumatology, uveitis surveillance, rehabilitation and treat-to-target medicine before irreversible joint damage.
- JIA is arthritis beginning before age 16, persisting for at least six weeks and remaining unexplained after infection, malignancy and other inflammatory disease are excluded.
- Inflammatory clues are joint swelling, warmth, restricted movement, morning stiffness and improvement with activity; young children may limp or stop using a limb without reporting pain.
- Classify oligoarticular, polyarticular RF-positive or negative, systemic, enthesitis-related, psoriatic and undifferentiated disease because risks and treatment differ.
- No blood test diagnoses JIA: ESR and CRP measure inflammation, ANA estimates uveitis risk, RF and anti-CCP refine phenotype and HLA-B27 supports selected enthesitis-related presentations.
- Use ultrasound to detect effusion and synovitis and MRI for deep joints, sacroiliac disease, marrow or structural questions; aspirate urgently when infection is possible.
- Refer suspected persistent inflammatory arthritis promptly to paediatric rheumatology and begin physiotherapy, occupational therapy and school support rather than waiting six weeks to make a referral.
- Oligoarticular disease often responds to intra-articular corticosteroid, while persistent polyarthritis generally requires early weekly methotrexate and treat-to-target monitoring.
- Escalate inadequate disease control to a biologic matched to subtype, uveitis and prior treatment; do not allow repeated steroid courses to substitute for disease-modifying therapy.
- Schedule slit-lamp screening from diagnosis according to age, ANA, subtype and disease duration because uveitis is commonly painless and externally invisible.
- Immunisation, infection screening, contraception when age-relevant, growth, bone, mental health and transition belong in every long-term treatment plan.
Key red flags
Acutely painful hot swollen joint with fever or refusal to move is septic arthritis until urgently assessed.
Night pain, bone tenderness, weight loss, bruising, pallor, lymphadenopathy, hepatosplenomegaly or cytopenia raises leukaemia or other malignancy.
Red painful photophobic eye or reduced vision requires same-day ophthalmology, but JIA uveitis is often asymptomatic and must be screened before symptoms.
Persistent quotidian fever, evanescent rash, serositis or organ enlargement suggests systemic JIA and creates macrophage-activation risk.
Back pain, enthesitis, hip arthritis, inflammatory bowel symptoms or acute anterior uveitis suggests enthesitis-related arthritis and spondyloarthritis spectrum.
Growth faltering, leg-length difference, contracture or delayed puberty indicates sustained inflammation or treatment toxicity requiring accelerated control.
Investigation priorities
Assess inflammation, anaemia, cytopenia and malignant or infectious warning features.
Management branches
Arthritis accompanies fever, severe pain, systemic illness or malignancy clues.
- Arrange urgent paediatric and orthopaedic assessment with FBC film, cultures and imaging.
- Aspirate and treat possible septic arthritis before any intra-articular corticosteroid.
- Escalate cytopenia, night pain, bruising or organ enlargement through malignancy pathways.