What is the best management approach for dermatomyositis?

Management of Dermatomyositis

The best management approach for dermatomyositis involves high-dose corticosteroids combined with methotrexate as initial therapy, followed by a structured treatment escalation protocol for refractory cases. 1

Initial Assessment and Referral

• All patients with suspected dermatomyositis should be referred to a specialized center with expertise in this condition 1
• High-risk patients need immediate/urgent referral, including those with severe disability, dysphagia, gastrointestinal vasculitis, myocarditis, lung disease, CNS involvement, skin ulceration, or requiring ICU management 1
• Disease activity should be assessed regularly using standardized tools for muscle strength (CMAS, MMT), skin involvement (CAT), and major organ involvement 1

First-Line Treatment

• Initial therapy should consist of high-dose corticosteroids combined with methotrexate 1

  • Methylprednisolone pulse (15-30 mg/kg/dose for 3 consecutive days), followed by oral prednisolone (1-2 mg/kg/day) 1
  • Methotrexate 15-20 mg/m²/week (maximum 40 mg/week), preferably administered subcutaneously 1
  • Corticosteroid dose should be gradually tapered as the patient shows clinical improvement 1

• Sun protection is essential for all patients with dermatomyositis 1

• A safe and appropriate exercise program monitored by a physiotherapist should be included in treatment 1

Treatment for Refractory Disease

For Mild-Moderate Disease with Inadequate Response:

• Check medication adherence and tolerance 1
• If intolerant to methotrexate, change to another DMARD such as mycophenolate mofetil (MMF) or ciclosporin A 1
• Consider adding IVIG, particularly when skin features are prominent 1

For Severe Disease:

• Consider adding cyclophosphamide 500-1000 mg/m² IV monthly for patients with major organ involvement or extensive ulcerative skin disease 1
• For persistent disease activity, consider:
  • Rituximab (B-cell depletion therapy), noting it may take up to 26 weeks to work 1
  • Anti-TNF therapies (infliximab or adalimumab are preferred over etanercept) 1
  • Combination therapy with high-dose MTX, ciclosporin A, and IVIG 1

Management of Skin Disease

• Ongoing skin disease reflects ongoing systemic disease and should be treated by increasing systemic immunosuppression 1
• Topical tacrolimus (0.1%) or topical steroids may help localized skin disease, particularly for symptomatic redness or itching 1
• For calcinosis (developing or established), intensification of immunosuppressive therapy should be considered 1

Monitoring and Follow-up

• Regular assessment of muscle strength, skin disease, and major organ involvement is essential 1
• Patient/parent-reported outcome measures should be used during disease monitoring 1
• Disease damage should be assessed at least yearly using a standardized measure such as the Myositis Damage Index 1

Treatment Duration and Discontinuation

• There is no high-level evidence regarding when to stop immunosuppressive therapy 1
• Consider withdrawing treatment if a patient has been off steroids and in remission on methotrexate (or alternative DMARD) for a minimum of 1 year 1

Special Considerations

• For juvenile dermatomyositis, the treatment approach follows similar principles but with age-appropriate dosing 1
• Adult dermatomyositis may be associated with malignancy, requiring thorough evaluation 2
• The multidisciplinary team should include physiotherapists and specialist nurses in addition to rheumatologists 1

Common Pitfalls to Avoid

• Delaying treatment intensification in patients with inadequate response (should be considered within the first 12 weeks) 1
• Underestimating skin disease, which reflects ongoing systemic inflammation 1
• Failing to recognize and treat calcinosis aggressively 1
• Inadequate monitoring of disease activity in all affected organ systems 1