What is the recommended treatment approach for a patient with juvenile arthritis?

Treatment of Juvenile Idiopathic Arthritis

Initial Treatment Strategy

Start with methotrexate as first-line DMARD therapy for polyarticular JIA, strongly preferred over NSAID monotherapy alone. 1

Polyarticular JIA (Multiple Joint Involvement)

• Initial therapy with a DMARD is strongly recommended over NSAID monotherapy (moderate evidence), with methotrexate as the preferred first-line agent 1, 2
• Subcutaneous methotrexate is conditionally recommended over oral methotrexate to optimize absorption and efficacy 1
• Methotrexate monotherapy is conditionally recommended over triple DMARD therapy as initial treatment (low evidence) 1
• NSAIDs are conditionally recommended only as adjunct therapy, not as monotherapy (very low evidence) 1

For patients with risk factors (high-risk joint involvement, high disease activity, or risk of disabling joint damage), initial biologic therapy may be considered, though DMARD therapy is still conditionally recommended first 2

Oligoarticular JIA (Few Joints Involved)

• A trial of scheduled NSAIDs is conditionally recommended as part of initial therapy 2
• Intraarticular glucocorticoid injections (IAGCs) are strongly recommended as part of initial therapy 2
• Triamcinolone hexacetonide is strongly recommended over triamcinolone acetonide for intraarticular injections (moderate evidence) 1
• Oral glucocorticoids are conditionally recommended against as initial therapy 2
• If inadequate response to NSAIDs and/or IAGCs, methotrexate is conditionally recommended as the preferred csDMARD 2

Systemic JIA (Fever, Rash, Systemic Features)

• NSAIDs are conditionally recommended as initial monotherapy 2
• Oral glucocorticoids are conditionally recommended against as initial monotherapy 2
• Conventional synthetic DMARDs are strongly recommended against as initial monotherapy 2
• IL-1 inhibitors or IL-6 inhibitors are strongly recommended over conventional synthetic DMARDs for inadequate response to NSAIDs and/or glucocorticoids, with no preferred agent between IL-1 and IL-6 inhibitors 2, 3

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Escalation of Therapy

For Polyarticular JIA with Inadequate Response to Methotrexate

• Adding a biologic to the original DMARD is conditionally recommended over changing to a second DMARD or triple DMARD therapy 2, 4
• Combination therapy with a biologic (etanercept, adalimumab, golimumab, abatacept, or tocilizumab) plus DMARD is conditionally recommended over biologic monotherapy (very low to moderate evidence, with adalimumab having moderate evidence) 1
• Combination therapy with a DMARD is strongly recommended for infliximab (low evidence) 1
• An adequate trial of methotrexate is considered 3 months; if no or minimal response after 6-8 weeks, changing or adding therapy is appropriate 1, 2

For Patients Failing First Biologic

• Switching to a non-TNF biologic (tocilizumab or abatacept) is conditionally recommended over switching to a second TNF inhibitor (very low evidence) 2

For Low Disease Activity (cJADAS-10 ≤2.5)

• Escalating therapy is conditionally recommended over no escalation, with options including intraarticular glucocorticoid injections, optimization of DMARD dose, trial of methotrexate if not done, and adding or changing biologic 2

For Moderate/High Disease Activity (cJADAS-10 >2.5)

• Adding a biologic to original DMARD is conditionally recommended over changing to a second DMARD 2

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Glucocorticoid Use: Critical Guidance

• Bridging therapy with a limited course of oral glucocorticoid (<3 months) during initiation or escalation of therapy in patients with high or moderate disease activity is conditionally recommended (very low evidence) 1
• Conditionally recommend against bridging therapy with oral glucocorticoid in patients with low disease activity (very low evidence) 1
• Strongly recommend against adding chronic low-dose glucocorticoid, irrespective of risk factors or disease activity 1, 2, 4

Critical Pitfall: Chronic glucocorticoid use causes growth suppression and osteoporosis in children—this must be avoided 4

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FDA-Approved Biologic Dosing

Adalimumab (HUMIRA) for Polyarticular JIA

For patients ≥2 years of age, dosing is weight-based 5:

• 10 kg to <15 kg: 10 mg every other week
• 15 kg to <30 kg: 20 mg every other week
• ≥30 kg: 40 mg every other week
• Can be used alone or in combination with methotrexate 5

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Adjunctive Therapies

• Physical therapy and/or occupational therapy are conditionally recommended for patients who have or are at risk of functional limitations (low to very low evidence) 1, 2, 4
• Methotrexate, glucocorticoids, NSAIDs, and/or analgesics may be continued during treatment with biologics 1, 5

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Disease Activity Monitoring

• Use validated disease activity measures such as cJADAS-10 to guide treatment decisions and facilitate treat-to-target approaches 2, 4
• Low disease activity is defined as cJADAS-10 ≤2.5 with ≥1 active joint 2
• Moderate/high disease activity is defined as cJADAS-10 >2.5 2
• Target low disease activity or inactive disease 4
• Early treatment initiation is critical to improve long-term outcomes and prevent permanent joint damage 2, 4

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Critical Pitfalls to Avoid

• Do not use NSAID monotherapy as initial therapy for polyarticular JIA—DMARD therapy is strongly recommended (moderate evidence) 2
• Do not use conventional synthetic DMARDs as initial monotherapy for systemic JIA—they are strongly recommended against 2
• Do not use chronic low-dose oral glucocorticoids—they are strongly recommended against irrespective of disease activity 2, 4
• Do not delay DMARD initiation in polyarticular disease, as early aggressive treatment prevents permanent joint damage 4