🎙️ Deep Dive: Juvenile Idiopathic Arthritis (JIA) – MSRA Essentials
In this focused episode, we break down Juvenile Idiopathic Arthritis (JIA) — a challenging yet high-yield topic for the MSRA exam. Whether you're revising for the MSRA, encountering paediatric rheumatology in clinic, or just want to reinforce your knowledge, we cover all the key facts in a memorable and exam-friendly format. ✅

🧠 What You'll Learn About JIA
• 📌 Definition: Chronic joint inflammation starting before age 16, lasting ≥6 weeks
• 🧬 Cause: Idiopathic – but involves immune dysfunction triggered by genetic & environmental factors
• 🩺 Subtypes:
 • Oligoarticular – ≤4 joints, ANA+ → ↑ uveitis risk
 • Polyarticular RF− / RF+ – ≥5 joints; RF+ = poorer prognosis
 • Systemic JIA – Fevers, rash, hepatosplenomegaly, serositis
 • Psoriatic arthritis – Arthritis + psoriasis or nail/digit signs
 • Enthesitis-related – Inflammation at tendon insertions, HLA-B27+
 • Undifferentiated – Doesn’t fit others neatly

🧪 Investigations
• Inflammatory markers: CRP, ESR
• ANA – for uveitis risk (esp. in oligoarticular)
• RF – to distinguish polyarticular subtypes
• HLA-B27 – for enthesitis-related JIA
• Ultrasound/MRI – better than X-ray early on
• Rule out differentials: Septic arthritis, malignancy, trauma, reactive arthritis

💊 Management – NICE-Aligned

Treatment TypeExamples & NotesNSAIDsIbuprofen, naproxen – symptom reliefDMARDsMethotrexate (1st-line), sulfasalazineBiologicsTNF-inhibitors: etanercept, adalimumabSteroidsIntra-articular or short-course oral useNon-drugPhysio, OT, hydrotherapy, eye screening