What is the initial approach to treating panniculitis?

Initial Approach to Treating Panniculitis

The initial approach to treating panniculitis should include testing for alpha-1 antitrypsin (AAT) deficiency, as augmentation therapy with purified human AAT or fresh frozen plasma is the most effective treatment for AAT deficiency-associated panniculitis, while corticosteroids, antibiotics, and cytostatic drugs are ineffective in this form. 1

Diagnostic Evaluation Before Treatment

Before initiating treatment, proper diagnosis is essential:

• Obtain deep excisional biopsy with large amount of tissue for histopathological evaluation 1
• Determine whether panniculitis is predominantly septal or lobular 2
• Check for presence or absence of vasculitis 2
• Test plasma AAT levels in all cases of biopsy-proven severe panniculitis, particularly factitious and necrotizing cases 1
• Consider microbiological analysis of skin biopsy to rule out infectious causes 2
• Check for T-cell clonal expansion if T-cell lymphoma is suspected 2

Treatment Algorithm Based on Panniculitis Type

1. AAT Deficiency-Associated Panniculitis

• First-line treatment: Augmentation therapy with purified human AAT or fresh frozen plasma 1
• Alternative for less severe cases: Dapsone alone or combined with augmentation therapy 1
• Important note: Corticosteroids, antibiotics, and cytostatic drugs are ineffective 1
• Additional measures:
  • Family screening for AAT deficiency
  • Antismoking counseling 1

2. Erythema Nodosum (Most Common Septal Panniculitis)

• First-line treatment: Nonsteroidal anti-inflammatory drugs (NSAIDs) 3
• Identify and treat underlying cause if possible 4
• For typical presentation, skin biopsy may not be required 2

3. Vasculitic Panniculitis (e.g., Leukocytoclastic Vasculitis)

• Initial treatment: Prednisone 1 mg/kg/day (up to 80 mg/day) for 1 month before tapering 5
• For severe cases: IV pulse methylprednisolone 500-1000 mg/day for 3-5 days before transitioning to oral prednisone 5
• Tapering schedule:
  • First 3 months: Do not reduce below 15 mg/day, taper by 10-15% every 1-2 weeks if improving
  • Months 3-6: Aim for moderate-dose (0.25-0.5 mg/kg/day, 10-40 mg/day)
  • After 6 months: Target low-dose (≤10 mg/day) with complete withdrawal if possible 5
• For refractory cases (defined as continued disease after 3 weeks of prednisone): Consider cyclophosphamide 5
• For chronic/relapsing cases: Consider steroid-sparing agents like azathioprine (2 mg/kg/day) or methotrexate (up to 25 mg/week) 5

4. Lupus Panniculitis

• First-line treatment: Corticosteroids with or without azathioprine 3
• Consider adding hydroxychloroquine to the treatment regimen 6

Monitoring and Follow-up

• Assess for new lesions and healing of existing lesions every 1-2 weeks during initial treatment 5
• Monitor for steroid-related adverse effects if using corticosteroids:
  • Blood pressure
  • Blood glucose
  • Weight changes
  • Mood alterations
  • Signs of infection 5
• Consider repeat skin biopsy if diagnosis remains uncertain or if treatment response is poor 2

Important Clinical Pitfalls to Avoid

1. Misdiagnosis: Do not rely solely on clinical presentation; histopathological confirmation is essential for most panniculitis types 3

2. Overlooking AAT deficiency: Testing for AAT deficiency is crucial as treatment differs significantly from other forms of panniculitis 1

3. Inappropriate steroid use: Corticosteroids are ineffective for AAT deficiency-associated panniculitis but are first-line for many other types 1, 5

4. Inadequate biopsy: Ensure deep excisional biopsy with sufficient tissue for proper histopathological evaluation 1, 2

5. Failure to identify underlying cause: Many panniculitides are secondary to systemic conditions that require specific treatment 4, 2

6. Inadequate follow-up: Some panniculitides may evolve or recur, requiring ongoing monitoring and potential treatment adjustments 2