What are the treatment options for Enthesitis-related Psoriatic Arthritis (PsA)?

Treatment Options for Enthesitis-related Psoriatic Arthritis (PsA)

For enthesitis in psoriatic arthritis, treatment should follow a step-wise approach based on severity, with NSAIDs and physical therapy for mild cases, DMARDs for moderate cases, and TNF inhibitors for severe or refractory cases. 1

Diagnosis and Assessment

• Enthesitis diagnosis is challenging and can be confirmed through clinical examination (pain/tenderness/swelling at tendon, ligament, or capsule insertion sites), ultrasound with power Doppler, or MRI 1
• Visual analogue pain scale can be used as an assessment modality for monitoring treatment response 1
• Common enthesitis sites include the heel (Achilles tendon insertion), but can occur at any insertion of an enthesis into bone 2

Treatment Algorithm Based on Severity

Mild Enthesitis

• First-line treatment: NSAIDs, physical therapy, and local corticosteroid injections 1, 3
• NSAIDs should be used as initial therapy for symptom control 3, 2
• Physical therapy helps maintain function and reduce pain 1, 2
• Corticosteroid injections should be considered with caution:
  • Perientheseal injections are preferred over intraentheseal injections 4
  • Ultrasound guidance is strongly recommended for proper needle placement 4
  • Avoid in high-risk patients with tendon rupture 4

Moderate Enthesitis

• First-line treatment: Disease-modifying antirheumatic drugs (DMARDs) 1, 3
• Common DMARDs used include:
  • Methotrexate (especially when significant skin involvement exists) 3, 5
  • Sulfasalazine 3, 5
  • Leflunomide 3, 5
  • Cyclosporine 5
• Note: The efficacy of DMARDs specifically for enthesitis is controversial, with limited evidence supporting their use 5, 2

Severe or Refractory Enthesitis

• First-line treatment: TNF inhibitors 1, 3
• TNF inhibitors with demonstrated efficacy include:
  • Infliximab 1
  • Etanercept 1, 6
  • Adalimumab 1, 7
• TNF inhibitors are highly effective for enthesitis in randomized controlled trials 2, 8
• Etanercept (Enbrel) is administered as 50 mg weekly subcutaneously for PsA 6

Important Clinical Considerations

Monitoring and Assessment

• Regular assessment of disease activity is essential to guide therapy adjustments 3
• Treatment should aim at reaching remission or low disease activity 3
• Poor prognostic factors include polyarticular disease, elevated ESR, previous treatment failures, existing joint damage, and diminished quality of life 3

Potential Pitfalls and Caveats

• TNF inhibitors carry risks of serious infections and malignancies 6
• Before starting TNF inhibitors:
  • Screen for latent tuberculosis 6
  • Complete all age-appropriate vaccinations 6
  • Assess for active infections 6
• Avoid live vaccines while on TNF inhibitor therapy 6
• DMARDs have not demonstrated efficacy in inhibiting joint erosions in controlled studies 5
• Diagnostic ultrasound is advised before corticosteroid injection to confirm inflammation and rule out rupture 4

Treatment of Associated Conditions

• For patients with concurrent peripheral arthritis, the same step-wise approach applies, with NSAIDs for mild disease and progression to DMARDs and TNF inhibitors as needed 1, 3
• For patients with significant skin involvement, consider methotrexate or TNF inhibitors which address both skin and joint manifestations 3, 7
• For axial disease, NSAIDs and physiotherapy are first-line, with TNF inhibitors for inadequate response 1, 3

Enthesitis is an important manifestation of PsA that can significantly impact function and quality of life. Early recognition and appropriate treatment based on severity can help prevent disease progression and improve outcomes 8, 9.