What is cutaneous vasculitis and how is it managed?

Cutaneous Vasculitis: Description and Management

Cutaneous vasculitis is an inflammatory disease affecting blood vessel walls in the skin that requires prompt diagnosis and treatment with immunosuppressive therapy tailored to disease severity, ranging from colchicine for mild cases to cyclophosphamide or rituximab for severe or systemic involvement.

Definition and Clinical Presentation

Cutaneous vasculitis is characterized by inflammation and destruction of blood vessel walls in the skin, which can occur as an isolated phenomenon or as part of systemic vasculitis. The clinical presentation depends on the size and depth of vessels affected:

• Small vessel involvement (superficial):

  • Palpable purpura (most common)
  • Urticarial lesions
  • Papules
  • Vesicles

• Medium/deep vessel involvement:

  • Nodules
  • Livedo racemosa
  • Deep ulcers
  • Digital gangrene
  • Erythematous plaques

Classification

Cutaneous vasculitis can be classified as:

1. Primary (idiopathic):

   • Cutaneous leukocytoclastic angiitis
   • ANCA-associated vasculitis with skin involvement

2. Secondary:

   • Connective tissue disease-associated (lupus, rheumatoid arthritis)
   • Infection-associated
   • Drug-induced
   • Malignancy-associated

Diagnosis

Essential Diagnostic Tests

• Complete blood count
• Renal function tests
• Urinalysis
• Inflammatory markers (ESR, CRP)
• ANCA testing 1

Biopsy

• Critical for diagnosis: Deep excisional biopsy extending to subcutis from the most tender, reddish, or purpuric lesion 1, 2

• Histopathological findings:

  • Leukocytoclastic vasculitis (neutrophilic infiltration, nuclear debris)
  • Fibrinoid necrosis of vessel walls
  • Extravasation of red blood cells

• Direct immunofluorescence: Helps distinguish IgA-associated vasculitis (Henoch-Schönlein purpura) from IgG/IgM-associated vasculitis 2

Imaging

Based on suspected vessel size involvement:

• Small vessel: MRI/MRA or FDG-PET/CT
• Medium vessel: CTA of affected regions 1

Management

Treatment approach depends on disease severity, extent of involvement, and underlying cause:

1. Mild, Limited Cutaneous Disease

• Conservative measures:

  • Leg elevation
  • Avoidance of prolonged standing
  • NSAIDs for symptomatic relief 2, 3

• First-line pharmacologic therapy:

  • Colchicine
  • Dapsone 2, 3, 4

2. Moderate Cutaneous Disease

• Systemic corticosteroids (prednisone) 1, 3
• Steroid-sparing agents for persistent disease 1

3. Severe Cutaneous Disease or Systemic Involvement

• High-dose corticosteroids plus:

  • Cyclophosphamide (traditional first-line for severe disease)
  • Rituximab (preferred for younger patients, fertility concerns, or relapsing disease) 1, 5

• For ANCA-associated vasculitis:

  • Rituximab has shown 64% complete remission rate at 6 months compared to 53% with cyclophosphamide 5

4. Refractory Disease

• Plasma exchange
• Intravenous immunoglobulin
• Biologic agents 1, 2

Monitoring and Follow-up

• Regular assessment of disease activity using validated tools (Birmingham Vasculitis Activity Score)
• Monitoring of ANCA levels in ANCA-associated vasculitis
• Regular urinalysis and renal function tests to detect kidney involvement
• Vigilance for treatment complications, especially infections 1

Special Considerations

• Alpha-1 antitrypsin deficiency: Associated with cutaneous vasculitis; may respond dramatically to administration of purified AAT 6

• Neutropenic patients: At risk for ecthyma gangrenosum, a form of cutaneous vasculitis typically associated with Pseudomonas aeruginosa but can occur with other pathogens 6

• Treatment duration:

  • Limited cutaneous disease: 3-6 months
  • Systemic disease: Induction followed by maintenance therapy 1

Common Pitfalls to Avoid

• Delaying treatment in rapidly deteriorating patients
• Misdiagnosing pseudovasculitis (thrombotic disorders like antiphospholipid syndrome)
• Underestimating systemic involvement
• Failing to recognize ANCA-negative vasculitis 1

For optimal outcomes, patients with suspected or confirmed ANCA-associated vasculitis should be treated at centers with experience in vasculitis management 1.