What are the criteria for active morphea?

Criteria for Active Morphea

Active morphea is diagnosed by identifying inflammatory lesions in the most active sclerotic areas, which should be evaluated using standardized assessment tools like the Localized Scleroderma Cutaneous Assessment Tool (LoSCAT) that includes specific measures for disease activity. 1

Clinical Features of Active Morphea

• Active morphea presents with inflammatory signs including erythema, warmth, violaceous color, and induration at the border of lesions 1, 2
• The most active sclerotic areas should be carefully examined as they represent the sites of ongoing disease activity 1
• Disease activity may manifest as new lesions appearing or existing lesions expanding in size or depth 3, 2
• Active lesions may show progressive skin thickening and hardening due to increased collagen deposition 4

Standardized Assessment Tools

• The Localized Scleroderma Cutaneous Assessment Tool (LoSCAT) is recommended for standardized assessment of morphea activity 1
• LoSCAT includes:
  • Localized Scleroderma Skin Severity Index (LoSSI) - specifically measures disease activity 1
  • Localized Scleroderma Skin Damage Index (LoSDI) - measures permanent damage 1
• The LoSSI component evaluates erythema, skin thickness, and new lesion/lesion extension as markers of active disease 3

Diagnostic Confirmation

• Skin biopsy should be taken from the most active sclerotic area when there is diagnostic uncertainty or atypical features 1
• Biopsy is particularly important when there are features mimicking other conditions such as lichen sclerosus 5
• Histopathological examination helps determine the depth and degree of involvement, which is crucial for assessing activity 3
• Active morphea shows histological evidence of inflammation with lymphocytic infiltrates in the dermis and subcutaneous tissue 2

Monitoring Disease Activity

• Regular clinical assessment using LoSCAT is essential to monitor disease activity and treatment response 1
• Active disease may progress slowly and requires careful monitoring to prevent permanent cosmetic and functional sequelae 2, 6
• Morphea activity can be classified as mild, moderate, or severe based on standardized scoring systems 3
• Active disease typically requires more aggressive treatment approaches compared to stable disease 1, 2

Clinical Implications

• Identifying active morphea is critical as it guides treatment decisions - active, potentially disfiguring or disabling forms require systemic therapy 1
• The American College of Rheumatology recommends methotrexate combined with systemic corticosteroids for active morphea 1
• Treatment should be maintained for at least 12 months after achieving clinical improvement before tapering 1
• Failure to recognize and treat active disease can lead to permanent cosmetic disfigurement and functional disability 4, 6

Common Pitfalls in Diagnosis

• Mistaking morphea for other conditions such as lichen sclerosus, especially in extragenital sites 5
• Failing to distinguish between active inflammatory disease and residual damage from previous disease activity 1
• Inadequate assessment of the full extent of disease, which may involve deeper tissues including fascia, muscle, and bone 2
• Delaying treatment of active disease, which can lead to irreversible tissue damage and functional impairment 4, 7