What is the recommended management of juvenile idiopathic arthritis in children, including first‑line non‑steroidal anti‑inflammatory drugs, disease‑modifying antirheumatic drugs, biologic agents, intra‑articular steroids, and monitoring?

Management of Juvenile Idiopathic Arthritis

For polyarticular JIA, start subcutaneous methotrexate as first-line DMARD therapy, add NSAIDs for symptom control, use intraarticular triamcinolone hexacetonide for accessible joints, and escalate to biologic DMARDs (combined with methotrexate) if inadequate response after 3 months. 1

Initial Treatment Strategy by JIA Subtype

Polyarticular JIA (RF+ or RF-, Extended Oligoarticular)

• DMARD therapy is strongly recommended over NSAID monotherapy as initial treatment 1
• Methotrexate is the preferred first-line DMARD, conditionally recommended over leflunomide or sulfasalazine 1
• Subcutaneous methotrexate is conditionally recommended over oral formulation due to superior bioavailability 1
• NSAIDs are conditionally recommended as adjunctive therapy only, not as monotherapy 1
• Intraarticular glucocorticoids are conditionally recommended as adjunct therapy 1
• Triamcinolone hexacetonide is strongly recommended over triamcinolone acetonide for intraarticular injections (moderate evidence) 1
• **Bridging oral glucocorticoids (<3 months) are conditionally recommended during DMARD initiation** in patients with moderate/high disease activity (cJADAS-10 >2.5) 1
• Chronic low-dose oral glucocorticoids are strongly recommended AGAINST, regardless of disease activity or risk factors, due to growth suppression and osteoporosis 1

Oligoarticular JIA (Persistent or Extended)

• Trial of scheduled NSAIDs is conditionally recommended as initial therapy 1
• Intraarticular glucocorticoids are strongly recommended as part of initial therapy 1
• Oral glucocorticoids are conditionally recommended AGAINST as initial therapy 1
• Conventional synthetic DMARDs are strongly recommended if inadequate response to NSAIDs and/or intraarticular glucocorticoids, with methotrexate conditionally recommended as preferred agent over leflunomide, sulfasalazine, and hydroxychloroquine 1
• Biologic DMARDs are strongly recommended if inadequate response to NSAIDs/intraarticular glucocorticoids AND at least one conventional synthetic DMARD 1

Systemic JIA (Without Macrophage Activation Syndrome)

• NSAIDs are conditionally recommended as initial monotherapy 1
• Conventional synthetic DMARDs are strongly recommended AGAINST as initial monotherapy 1
• IL-1 inhibitors or IL-6 inhibitors are strongly recommended over conventional synthetic DMARDs for inadequate response to NSAIDs and/or glucocorticoids 1
• There is no preferred agent between IL-1 and IL-6 inhibitors 1

Enthesitis-Related Arthritis and Sacroiliitis

• NSAIDs and intraarticular glucocorticoids are recommended as initial therapy 1
• Conventional synthetic DMARDs (methotrexate preferred) are strongly recommended for inadequate response 1
• Biologic DMARDs (TNF inhibitors) are conditionally recommended after failure of at least one conventional synthetic DMARD 1

Treatment Escalation Algorithm

For Polyarticular JIA with Inadequate Response to Methotrexate

An adequate trial of methotrexate is 3 months; changing or adding therapy is appropriate if minimal response after 6-8 weeks 1

• Combination therapy with a biologic DMARD plus methotrexate is conditionally recommended over biologic monotherapy 1
  • Etanercept, adalimumab, golimumab, abatacept, or tocilizumab can be added to methotrexate 1
  • Infliximab requires combination with a DMARD (strong recommendation) 1
• Adding a biologic to original DMARD is conditionally recommended over switching to a second DMARD or triple DMARD therapy 1

For Patients Failing First Biologic

• Switching to a non-TNF biologic (tocilizumab or abatacept) is conditionally recommended over switching to a second TNF inhibitor 1

For Low Disease Activity (cJADAS-10 ≤2.5 with ≥1 active joint)

• Escalating therapy is conditionally recommended over no escalation 1
• Options include: optimizing DMARD dose, adding intraarticular glucocorticoids, or adding/changing biologic 1

Disease Activity Monitoring

Use the clinical Juvenile Arthritis Disease Activity Score based on 10 joints (cJADAS-10) to guide treat-to-target approach 1, 2

• Low disease activity: cJADAS-10 ≤2.5 with ≥1 active joint 1
• Moderate/high disease activity: cJADAS-10 >2.5 1
• Target low disease activity or inactive disease 2, 3
• Validated disease activity measures are conditionally recommended to facilitate treat-to-target approaches 1

Risk Stratification

Consideration of risk factors for poor outcome is conditionally recommended to guide treatment decisions 1

Risk factors include: 1

• Involvement of ankle, wrist, hip, sacroiliac joint, and/or temporomandibular joint
• Presence of erosive disease or enthesitis
• Delay in diagnosis
• Elevated inflammatory markers (ESR, CRP)
• Symmetric disease
• Positive rheumatoid factor
• Positive anti-cyclic citrullinated peptide antibodies
• Joint damage

Adjunctive Therapies

Physical therapy and/or occupational therapy are conditionally recommended for patients who have or are at risk of functional limitations 1, 2, 3

Critical Pitfalls to Avoid

• NEVER use NSAID monotherapy as initial therapy for polyarticular JIA—DMARD therapy is strongly recommended 1, 2
• NEVER use chronic low-dose oral glucocorticoids regardless of disease activity—strongly recommended against due to growth suppression and osteoporosis 1, 2, 3
• NEVER use conventional synthetic DMARDs as initial monotherapy for systemic JIA—strongly recommended against 1
• Do not delay DMARD initiation in polyarticular disease—early aggressive treatment prevents permanent joint damage 2, 3
• Do not use bridging oral glucocorticoids in patients with low disease activity—conditionally recommended against 1

Monitoring Requirements

• Assess disease activity at each visit using cJADAS-10 1, 2
• Monitor for treatment response after 6-8 weeks of methotrexate initiation 1
• Screen for uveitis regularly, especially in oligoarticular JIA with ANA positivity 1
• Monitor for macrophage activation syndrome in systemic JIA 1
• Assess growth parameters and bone health in all patients, particularly those receiving glucocorticoids 1