What are the guidelines for treating Enteropathic Arthritis (ERA) in children?

From the Guidelines

The treatment of enthesitis-related arthritis (ERA) in children should start with non-steroidal anti-inflammatory drugs (NSAIDs) and may require the addition of tumor necrosis factor inhibitors (TNFi) for inadequate response, as recommended by the 2019 American College of Rheumatology guideline 1.

Initial Treatment

The initial treatment approach for ERA in children involves the use of NSAIDs, such as naproxen or indomethacin, for a period of 4-6 weeks.

• NSAIDs are recommended over no treatment with an NSAID, with a level of evidence rated as very low 1.
• The dosage for naproxen is typically 10-15 mg/kg/day divided twice daily, while indomethacin is used at 1-3 mg/kg/day divided 2-4 times daily.

Subsequent Treatment

If symptoms persist despite NSAID treatment, the next step involves the use of disease-modifying antirheumatic drugs (DMARDs) or biological agents.

• For children and adolescents with active enthesitis despite treatment with NSAIDs, using a TNFi is conditionally recommended over methotrexate or sulfasalazine, with a level of evidence rated as low 1.
• Bridging therapy with a limited course of oral glucocorticoids (<3 months) during initiation or escalation of therapy is conditionally recommended, with a level of evidence rated as very low 1.
• Physical therapy is essential throughout treatment to maintain joint mobility and muscle strength, with a level of evidence rated as very low 1.

Biological Agents

Biological agents, particularly TNF inhibitors such as etanercept, adalimumab, or infliximab, are recommended for inadequate response after 3 months of treatment with DMARDs.

• The use of TNFi is strongly recommended over continued NSAID monotherapy for children and adolescents with active sacroiliitis, with a level of evidence rated as low 1.
• The dosage for etanercept is typically 0.8 mg/kg weekly, while adalimumab is used at 24 mg/m² every 2 weeks, and infliximab at 3-6 mg/kg at weeks 0,2,6, then every 8 weeks.

Individualized Treatment

Treatment decisions should be individualized based on disease severity, axial involvement, and extra-articular manifestations.

• The goal is to achieve disease remission, prevent joint damage, and maintain normal growth and development 1.
• Early aggressive treatment is often necessary as ERA can be more resistant to therapy than other juvenile arthritis subtypes due to its association with HLA-B27 and tendency for axial involvement.

From the Research

Treatment Options for ERA in Children

• Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used in the treatment of ERA, however, their use should be carefully considered due to the potential risk of gastrointestinal toxicity 2
• Disease-modifying antirheumatic drugs (DMARDs) are also used in the treatment of ERA, often in combination with other medications 3
• Biologic agents, such as TNF-alpha inhibitors, are recommended for use in patients with axial disease and/or enthesitis 4
• Novel treatment agents, including IL-17/IL-23 or JAK/STAT pathways blockers, are also being explored as potential treatment options for ERA 4

Considerations for Treatment

• The treatment regimen for ERA should be individualized based on the specific needs and symptoms of the patient 3
• Patients with ERA should be closely monitored for signs of gastrointestinal toxicity, particularly if they are taking NSAIDs 2
• The use of selective COX-2 inhibitors may be a safer option for patients with ERA who require long-term NSAID use 2

Associated Conditions

• ERA is often associated with other conditions, such as inflammatory bowel disease (IBD) and ankylosing spondylitis 5, 6
• Patients with ERA should be screened for these associated conditions, and treatment should be tailored to address any related symptoms or complications 5, 6