urticarial vasculitis

Etiology

• serum sickness
• drug induced: ACE inhibitors, penicillin, sulfonamides, fluoxetine, & thiazides
• connective tissue disease (hypocomplementemic form)
  • systemic lupus erythematosus
• viral infection
  • hepatitis B, hepatitis C, infectious mononucleosis
• idiopathic (majority of cases)

Epidemiology

• male:female ratio is 1:2
• median age: 43 years, range: 15-90 years
• in serum sickness
  • occurs 8-14 days after antigen exposure in non- sensitized individuals
  • occurs within 36 hours in sensitized individuals
• relatively rare

Pathology

• histologically, changes of leukocytoclastic vasculitis
• perivascular neutrophilic infiltrate involving postcapillary venules
• expansion of the vessel wall occurs
• endothelium is intact
• deposition of complement & fibrin in the blood vessels &, occasionally, IgM, IgG, & IgA along the basement membrane
• extravasation of red blood cells
• eosinophils may be noted early
• later in the lesion's course, infiltrate may become a mixture of lymphocytes & neutrophils
• pulmonary vasculitis has NOT been demonstrated

Clinical manifestations

• urticarial lesions
  • erythematous wheals, circumscribed areas of edema
  • occasionally indurated
  • sometimes purpuric, petechiae
  • pruritus or burning
  • painful more than pruritic
  • individual lesions last up to 5 days
  • wheals hurt, burn or sting rather than itch & leave residual pigmentation (bruising) after they resolve
• lymphadenopathy
• arthralgias (60%), arthritis 28%
• fever
• abdominal pain (25%)
• glomerulonephritis (15%)

Laboratory

• serum complement levels
  • CH50, serum C3, serum C4, serum Clq
  • may be diminished or normal
• autoantibodies to C1q & vascular endothelial cells (hypocomplementemic form)
• antineutrophilic cytoplasmic antibodies rare
• renal function tests & urinalysis to evaluate effects of vasculitis on kidneys
• skin biopsy: (recent lesion, < 48 hours after onset)
  • confirms leukocytoclastic vasculitis
  • direct immunofluorescence may show deposition of vascular C3, fibrin, & immunoglobulins

Radiology

• chest x-ray for patients with hypocomplementemia & pulmonary symptoms

Complications

• greater incidence of coexisting disease in hypocomplementemic form:
  • angioedema
  • connective-tissue disease [primarily SLE]
  • COPD in 62% with hypocomplementemic form
    • many of these had been smokers
• nephritis

Differential diagnosis

• urticaria
  • lesions resolve faster (< 24 hours) & are less livid
  • itch more common than burning & stinging
  • wheals resolve without hyperpigmentation
  • no systemic symptoms, such as fever or joint pain

Management

• treatment is based on
  • systemic effects of the disease
  • extent of cutaneous involvement
  • previous response to treatment
• for patients with cutaneous involvement only
  • antihistamines
  • nonsteroidal anti-inflammatory drugs (NSAIDs)
  • for persistent cutaneous manifestations
    • hydroxychloroquine, colchicine, or dapsone
• for patients with systemic involvement or refractory disease
  • glucocorticoids
  • azathioprine
  • mycophenolate mofetil
  • rituximab
  • cyclophosphamide
• prognosis: good, most cases resolve in months to years

More general terms

• leukocytoclastic vasculitis

Additional terms

• urticaria (hives)

Patient information

urticarial vasculitis patient information