FFinalistSouthampton · 2027
Child health
AKT · Child health/Growth, GI & MSK

Juvenile idiopathic arthritis (JIA)

Chronic childhood arthritis (>6 weeks, onset <16y)

Overview

Arthritis persisting >6 weeks with onset before 16 years, of unknown cause, with several subtypes. Systemic JIA (Still disease) has the classic quotidian fever + salmon-pink rash; oligoarticular is the commonest and carries an uveitis risk.

Recognise

  • Joint swelling/stiffness >6 weeks; morning stiffness, limp
  • Oligoarticular (≤4 joints): commonest; ANTERIOR UVEITIS risk (ANA+) → needs slit-lamp screening
  • Systemic (Still): daily spiking fever, salmon-pink rash, hepatosplenomegaly, serositis
  • Polyarticular: ≥5 joints

Red flags

  • Eye involvement (uveitis often asymptomatic → screen); macrophage activation syndrome in systemic JIA

Differentials & how to tell them apart

Septic arthritis (paediatric)acute single hot joint, febrile, raised CRP — emergency, not chronic
Reactive arthritispost-infectious, self-limiting
Acute lymphoblastic leukaemia (ALL)bone pain + cytopenias can mimic — check the film
Transient synovitis (irritable hip)self-limits within 1–2 weeks, not >6 weeks

Investigations

Clinical (>6 weeks). Inflammatory markers, ANA (uveitis risk), rheumatoid factor (usually negative), exclude infection/malignancy; slit-lamp ophthalmology screening.

Management

NSAIDs + specialist paediatric rheumatology; uveitis screening

  1. 1Refer to paediatric rheumatology. NSAIDs + intra-articular steroids for symptom control.Gate: Oligoarticular / ANA-positive → regular slit-lamp screening: the uveitis is often ASYMPTOMATIC and sight-threatening
  2. 2Persistent/polyarticular/systemic → methotrexate then biologics; watch for macrophage activation syndrome in systemic JIA.
NSAIDs — first-line symptomatic
Intra-articular / systemic corticosteroids — flares
Methotrexate; biologics (anti-TNF, anti-IL-1/6) — DMARDs for persistent/systemic disease (specialist)

Key points

The uveitis of oligoarticular JIA is silent — screening prevents blindness. Systemic JIA = fever + salmon rash and can flare into macrophage activation syndrome.

Monitor & prognosis

Joint function, growth, eye screening, drug monitoring.

Many remit; uveitis and systemic disease drive morbidity.

Source: NICE; BSPAR (paediatric rheumatology)