Cutaneous Vasculitis: Clinical Manifestations and Management
Primary Clinical Manifestations
Palpable purpura is the hallmark cutaneous sign of vasculitis, representing inflammatory destruction of small blood vessels in the dermis. 1, 2
The clinical presentation varies significantly based on vessel size and depth of involvement:
Superficial Small Vessel Involvement (Most Common)
- Palpable purpura: Non-blanching, raised purpuric lesions that are tender to touch 1, 2
- Infiltrated erythema: Red, indurated patches or plaques 2
- Urticarial lesions: Hive-like lesions that persist >24 hours and may leave residual purpura 3
- Hemorrhagic vesicles or bullae: Fluid-filled lesions with blood content 3
Deep Dermal and Subcutaneous Vessel Involvement
- Nodular erythema: Deep, tender subcutaneous nodules 2
- Livedo racemosa: Irregular, net-like violaceous discoloration indicating deeper vessel involvement 2, 3
- Deep ulcerations: Painful, punched-out ulcers with necrotic bases 2, 3
- Digital gangrene: Tissue necrosis of fingers or toes 2, 3
Systemic Vasculitis-Specific Cutaneous Features
In polyarteritis nodosa (PAN), cutaneous manifestations include nodules and livedo reticularis as the most common presentations 4. These skin findings occur alongside systemic symptoms including fever, weight loss, and organ-specific manifestations 4.
In systemic necrotizing vasculitides with severe alpha-1 antitrypsin deficiency, cutaneous abnormalities are heterogeneous and include erythematous or necrotizing papules, vesicles, palpable purpura, subcutaneous nodules, erythematous plaques, and relapsing ulcerative panniculitis 4.
Special Presentation: Ecthyma Gangrenosum
Ecthyma gangrenosum represents cutaneous vasculitis caused by bacterial invasion of vessel walls, beginning as painless erythematous macules that rapidly become painful and necrotic within 12-24 hours 4. While classically associated with Pseudomonas aeruginosa in neutropenic patients, similar lesions occur with other organisms including Aeromonas, Serratia, Staphylococcus aureus, Candida, Aspergillus, and Fusarium 4.
Associated Systemic Symptoms
Cutaneous vasculitis rarely occurs in isolation when part of systemic disease:
- Constitutional symptoms: Fever, malaise, weight loss, arthralgias, myalgias 4
- Neurologic manifestations: Mononeuritis multiplex, peripheral neuropathy 4
- Renal involvement: Hypertension, hematuria, proteinuria 4
- Gastrointestinal symptoms: Abdominal pain, bleeding 4
Diagnostic Approach
Skin Biopsy Requirements
A deep excisional biopsy extending to the subcutis taken from the most tender, reddish or purpuric lesional skin is essential for accurate diagnosis 2. Serial sections are often required to identify the main vasculitic lesion 2.
Key histopathologic findings include:
- Leukocytoclastic vasculitis: Neutrophilic infiltration with nuclear debris (leukocytoclasis) in and around vessel walls 4
- Fibrinoid necrosis: Vessel wall destruction with fibrin deposition 4
- Mixed inflammatory infiltrates in medium vessel disease 4
Direct immunofluorescence should be performed concurrently to distinguish IgA-associated vasculitis (Henoch-Schönlein purpura) from IgG/IgM-associated vasculitis, which has prognostic significance 2.
Distinguishing Primary from Secondary Vasculitis
In adults, cutaneous vasculitis requires extensive workup as it may represent systemic necrotizing vasculitis, connective tissue disease, severe bacterial infection (especially endocarditis), or malignancy 5. Blood cultures are mandatory in any febrile patient with purpura, particularly with cardiac murmur 6, 5.
In contrast, children with cutaneous vasculitis predominantly have primary disease (Henoch-Schönlein purpura in 89% of cases), allowing a simpler diagnostic approach 5.
Treatment Strategy
Mild, Self-Limited Disease
For isolated cutaneous vasculitis without systemic involvement, initial conservative management includes leg elevation, avoidance of prolonged standing, and NSAIDs 1, 2, 3. Most cases represent self-limited phenomena resolving within 3-6 weeks 1.
Recurrent or Persistent Cutaneous Disease
For mild recurrent or persistent disease, colchicine and dapsone are first-choice agents 1, 2, 3. These should be reserved for symptomatic, recurrent, or extensive skin disease 3.
Severe Cutaneous or Systemic Disease
Severe cutaneous disease requires systemic corticosteroids, and systemic vasculitis mandates combination therapy with corticosteroids plus immunosuppression (cyclophosphamide, azathioprine, or methotrexate) 1, 2, 3.
For severe PAN specifically, early treatment with cyclophosphamide and glucocorticoids is recommended, with emphasis on limiting long-term exposure to minimize toxicity 4.
Refractory Disease
Plasmapheresis and intravenous immunoglobulin are viable options for refractory vasculitis 2, 3. Biologic therapies including TNF-alpha inhibitors (infliximab) and anti-B-cell antibodies (rituximab) show benefit in certain settings including ANCA-associated vasculitis and connective tissue disease-related vasculitis 2, 3.
Special Populations
In neutropenic patients with cutaneous vasculitis, hospitalization and empiric antibacterial therapy with vancomycin plus antipseudomonal antibiotics (cefepime, carbapenem, or piperacillin-tazobactam) are recommended 4. Treatment duration for most bacterial skin and soft tissue infections should be 7-14 days 4.
Critical Pitfalls to Avoid
- Never dismiss palpable purpura in adults as benign without excluding systemic necrotizing vasculitis, endocarditis, or malignancy 5
- Do not attribute cutaneous vasculitis solely to medications without excluding infectious causes, particularly in febrile patients 6
- Avoid superficial biopsies—inadequate tissue sampling misses deeper vessel involvement and leads to diagnostic error 2
- In patients with coexisting pan-dermal small-vessel and subcutaneous muscular-vessel vasculitis, strongly consider connective tissue disease, ANCA-associated vasculitis, Behçet disease, or malignancy-associated vasculitis 2