Treatment of Leukocytoclastic Vasculitis with Purpura
Immediately discontinue any suspected offending medication—this single intervention alone often induces complete resolution without requiring any immunosuppressive therapy. 1, 2
Initial Management: Drug Discontinuation is Key
The cornerstone of treatment is identifying and stopping the culprit drug upon clinical suspicion. 1, 2 This is critical because drug-induced leukocytoclastic vasculitis typically resolves spontaneously within weeks after drug withdrawal, often requiring only symptomatic management. 3
Common offending medications to consider: 1, 2
- Hydralazine
- Propylthiouracil
- Levamisole-adulterated cocaine
- Minocycline
- Levetiracetam
- Warfarin
Supportive measures: 3
- Compression stockings to reduce purpura
- Leg elevation
- Symptomatic treatment for pain
When to Add Systemic Corticosteroids
Add systemic corticosteroids (prednisolone 1 mg/kg/day, maximum 60 mg/day) ONLY when hemorrhagic blisters or signs of incipient skin necrosis appear. 1, 2, 3
Do not routinely use corticosteroids for isolated cutaneous disease presenting with simple palpable purpura without these severe features. 1 The disease often has a favorable course and aggressive therapy is unnecessary in most cases. 3
Treatment for Chronic or Relapsing Disease
For patients with chronic or relapsing cutaneous leukocytoclastic vasculitis, use colchicine 0.6 mg twice daily as first-line treatment. 1, 2, 3 Colchicine has an effective and better safety profile compared to long-term corticosteroids. 1, 2
If colchicine fails, consider dapsone as second-line therapy. 3 Systemic dapsone is effective but requires screening for glucose-6-phosphate dehydrogenase deficiency and routine monitoring of blood counts due to risks of neuropathy, blood dyscrasia, and hypersensitivity syndrome. 4 Topical dapsone may provide similar efficacy with fewer adverse effects in selected patients. 4
Critical Pitfall: Distinguishing Drug-Induced from ANCA-Associated Vasculitis
Do NOT treat drug-induced or isolated cutaneous leukocytoclastic vasculitis with cyclophosphamide or rituximab—these aggressive immunosuppressants are reserved exclusively for true ANCA-associated systemic vasculitis and carry significant toxicity. 1, 2
Diagnostic clues suggesting drug-induced (NOT systemic ANCA-associated vasculitis): 1, 2
- High-titer MPO-ANCA or dual MPO/PR3 positivity
- Discordance between ANCA immunofluorescence and ELISA results
- Positive ANA and antihistone antibodies
- Isolated cutaneous involvement without glomerulonephritis or pulmonary hemorrhage
- In levamisole-induced cases: neutropenia and retiform purpuric rash
Basic diagnostic work-up should include: 3, 5
- History of drug intake and preceding infections
- Skin biopsy with direct immunofluorescence
- Differential blood count
- Urinalysis (to assess for renal involvement)
- Throat swabs
- Cryoglobulins, serum protein electrophoresis, rheumatoid factor, antinuclear antibody, and ANCA testing depending on clinical presentation
When True Systemic Vasculitis is Present
For generalized ANCA-associated vasculitis with organ-threatening disease (glomerulonephritis, pulmonary hemorrhage), use cyclophosphamide (oral 2 mg/kg/day, max 200 mg/day, or intravenous pulses) combined with prednisolone 1 mg/kg/day (max 60 mg/day). 6, 1
Rituximab is an alternative to cyclophosphamide for remission induction in ANCA-associated vasculitis. 6, 1 These aggressive regimens apply only when systemic vasculitis is confirmed, not for isolated cutaneous or drug-induced disease. 1, 2
Prognosis and Follow-Up
Drug-induced leukocytoclastic vasculitis has a favorable prognosis with drug discontinuation alone. 1 The prognosis depends heavily on whether this is isolated cutaneous disease versus a component of systemic vasculitis—cutaneous leukocytoclastic vasculitis as a component of Henoch-Schönlein purpura has a much better prognosis than the same findings as a component of Wegener's granulomatosis. 5
When systemic vasculitis is the underlying cause, long-term follow-up and rapid access to specialist services are necessary. 6, 1 Patients with ANCA-associated vasculitis should be managed in close collaboration with, or at, centers of expertise. 6