What is the appropriate workup and treatment for a pediatric patient with suspected Juvenile Rheumatoid Arthritis (JRA)?

Workup for Juvenile Idiopathic Arthritis

Begin with scheduled NSAIDs immediately while expediting rheumatology referral, as early DMARD therapy is crucial to prevent permanent joint damage. 1

Initial Clinical Assessment

Identify poor prognostic features that mandate aggressive treatment:

• Joint involvement: ankle, wrist, hip, sacroiliac joint, or temporomandibular joint 2
• Erosive disease or enthesitis 2
• Elevated inflammatory markers (ESR, CRP) 1
• Symmetric disease pattern 2
• Delay in diagnosis 2

Laboratory Workup

Obtain baseline inflammatory markers:

• Complete blood count with differential 2
• Erythrocyte sedimentation rate (ESR) 1
• C-reactive protein (CRP) 1

Prior to initiating biologic therapy:

• Tuberculosis screening is conditionally recommended before starting biologic DMARDs and when TB exposure is suspected 3, 4

Imaging Studies

Radiography as a screening test is strongly recommended against for identifying active synovitis or enthesitis 3. Instead, ultrasound should be used to detect effusion and assess joint involvement 1.

Imaging guidance is conditionally recommended when performing intraarticular glucocorticoid injections 3.

Treatment Algorithm by JIA Subtype

Oligoarticular JIA (≤4 joints in first 6 months)

First-line therapy:

• Scheduled NSAIDs (not as-needed dosing) 2, 1, 3
• Intraarticular glucocorticoid injections strongly recommended 2, 1, 3
• Triamcinolone hexacetonide is strongly recommended as the preferred agent over other steroids 1
• Oral glucocorticoids are conditionally recommended against 2, 3

Second-line therapy (inadequate response to NSAIDs/IAGCs):

• Conventional synthetic DMARDs are strongly recommended 2, 3
• Methotrexate is conditionally recommended as first choice over leflunomide, sulfasalazine, and hydroxychloroquine (in that order) 2, 1, 3
• Subcutaneous methotrexate is conditionally recommended over oral formulation 1
• Adequate trial duration is 3 months, but consider changing therapy if minimal response after 6-8 weeks 1

Third-line therapy (failure of NSAIDs/IAGCs plus ≥1 conventional DMARD):

• Biologic DMARDs are strongly recommended 2, 3
• No preferred biologic agent 2

Polyarticular JIA (≥5 joints)

Initiate methotrexate as first-line disease-modifying therapy without delay 1. NSAIDs serve only as adjunct therapy 1.

Systemic JIA

First-line therapy:

• NSAIDs are conditionally recommended as initial monotherapy 2, 3
• Oral glucocorticoids are conditionally recommended against as initial monotherapy 2, 3
• Conventional synthetic DMARDs are strongly recommended against as initial monotherapy 2, 3

For inadequate response to NSAIDs/glucocorticoids:

• IL-1 and IL-6 inhibitors are strongly recommended over conventional synthetic DMARDs 1, 3

Enthesitis-Related Arthritis

First-line therapy:

• NSAIDs are strongly recommended 1
• Physical therapy is conditionally recommended for those with or at risk for functional limitations 1

For sacroiliitis:

• TNF inhibitors are strongly recommended 1

For persistent enthesitis despite NSAIDs:

• TNF inhibitors are conditionally recommended over methotrexate or sulfasalazine 1

Medication Monitoring Requirements

Methotrexate:

• CBC, liver function tests, and creatinine within first 1-2 months, then every 3-4 months 2, 3
• Folic or folinic acid supplementation is strongly recommended 2
• Decrease dose or withhold if clinically relevant LFT elevation or decreased neutrophil/platelet count 2

NSAIDs:

• CBC, liver function tests, and renal function every 6-12 months 2

TNF inhibitors:

• CBC and liver function tests within first 1-2 months, then every 3-4 months 3

Disease Activity Monitoring

Use validated disease activity measures to guide treatment decisions 2, 3:

• cJADAS-10 is recommended for treat-to-target approaches 1
• Low disease activity: cJADAS-10 ≤2.5 with ≥1 active joint 1
• Moderate/high disease activity: cJADAS-10 >2.5 1

Immunization Management

Complete all age-appropriate vaccinations prior to initiating immunosuppressive therapy 4.

For children not on immunosuppression:

• Live and inactivated vaccines are strongly recommended 3

For children on immunosuppression:

• Inactivated vaccines are strongly recommended 3
• Annual influenza vaccination is strongly recommended 3
• Live attenuated vaccines are conditionally recommended against 3

Adjunctive Therapies

Physical and occupational therapy are conditionally recommended regardless of pharmacologic therapy 2, 1.

Dietary recommendations:

• Discussion of healthy, age-appropriate diet is strongly recommended 2
• Use of specific diets to treat JIA is strongly recommended against 2
• Herbal interventions specifically to treat JIA are conditionally recommended against 2

Critical Pitfalls to Avoid

Never use prolonged oral glucocorticoids as monotherapy—only for short-term bridging (<3 months) during initiation of definitive therapy 1, 3. Doses higher than 50 mg per week of etanercept are not recommended based on increased adverse reactions without improved efficacy 4. Do not dismiss insidious onset joint pain as simple overuse without ruling out inflammatory arthritis, as delay in diagnosis is a poor prognostic factor 2, 1.