What is exercise-induced vasculitis and can it cause blistering?

Exercise-Induced Vasculitis: Clinical Features and Management

Exercise-induced vasculitis (EIV) is a distinct cutaneous condition characterized by erythematous or purpuric plaques on the lower legs that develop after prolonged exercise, especially in hot weather, and may present with symptoms including itching, pain, and burning sensations. 1

Clinical Characteristics

Presentation

• Primarily affects the lower legs, with a characteristic sparing of areas covered by compression socks or stockings 1
• Manifests as:
  • Erythematous plaques
  • Urticarial lesions
  • Purpuric patches
• Symptoms include:
  • Itching
  • Pain
  • Burning sensation

Triggers

• Prolonged exercise, especially in hot weather
• Common activities that trigger EIV:
  • Walking/hiking
  • Dancing
  • Swimming 1
  • Standing for extended periods 2

Demographics

• More common in females 3
• Can affect both adults and adolescents 4
• May occur in otherwise healthy individuals 1

Pathophysiology

EIV appears to result from:

• Acute failure of the calf muscle pump during prolonged exercise
• Thermoregulation decompensation in hot weather
• Venous stasis in the lower extremities 1

Diagnosis

Histopathology

• Leukocytoclastic vasculitis is present in approximately 95% of cases
• Immune deposits:
  • C3 deposits (88% of cases)
  • Immunoglobulin M deposits (46% of cases) 1

Differential Diagnosis

EIV should be distinguished from:

• Exercise-induced anaphylaxis (which presents with diffuse warmth, pruritus, erythema, urticaria, and can progress to angioedema, gastrointestinal symptoms, and vascular collapse) 5
• Cholinergic urticaria (characterized by small punctate wheals) 5
• Other forms of cutaneous vasculitis 2

Blistering in Exercise-Induced Vasculitis

While the primary literature on EIV does not specifically mention blistering as a common feature, the condition presents with inflammatory changes that can potentially lead to epidermal damage. The main presentations are erythematous, urticarial, or purpuric plaques 1, 3. If severe enough, these inflammatory changes could theoretically lead to blistering in some cases, though this is not highlighted as a typical feature in the available evidence.

Management

Immediate Measures

• Rest and elevation of affected legs 2
• Avoid prolonged standing 2
• Discontinue exercise at the earliest symptoms 1

Pharmacological Treatment

• Topical corticosteroids may help reduce symptoms 1
• NSAIDs can provide relief for mild cases 2
• For recurrent or persistent cases, consider:
  • Colchicine
  • Dapsone 2

Prevention Strategies

• Wear light, non-restrictive clothing 1
• Consider compression hosiery during exercise 3
• Avoid exercising in extreme heat when possible
• Manual lymphatic drainage may be helpful in some cases 3

Prognosis

• Lesions typically resolve spontaneously within approximately 10 days 1
• Recurrence is common (77.5% of cases) when triggering conditions persist 1
• No long-term sequelae have been reported in otherwise healthy individuals

Special Considerations

• In some cases, EIV may be associated with underlying autoimmune conditions 6
• Consider further evaluation if:
  • Symptoms are unusually severe or persistent
  • Patient has a personal or family history of autoimmune disorders
  • Vasculitic lesions appear in areas other than the lower extremities

EIV is often misdiagnosed or underreported despite being relatively common. Recognizing its characteristic presentation and association with exercise in hot weather can help clinicians make an accurate diagnosis and provide appropriate management.