What are the exam findings of leukocytoclastic vasculitis?

Exam Findings of Leukocytoclastic Vasculitis

The primary exam finding of leukocytoclastic vasculitis is palpable purpura, which is the most common cutaneous manifestation of this small vessel vasculitis. 1

Cutaneous Manifestations

• Palpable purpura - Most characteristic finding 1, 2
• Petechiae - Small, pinpoint hemorrhages 1
• Maculopapular rash - Flat and raised lesions 3
• Vesicles and bullae - In rare, severe cases 3
• Ulcerations - Can develop in more severe cases 4
• Distribution - Predominantly on the lower extremities, particularly the shins and ankles due to gravitational dependency 1, 3
• Less commonly affects buttocks, abdomen, upper extremities, and face 3

Systemic Manifestations

Depending on organ involvement, patients may present with:

• Fever - Indicating systemic inflammation 5
• Myalgia - Muscle pain 5
• Arthralgia/arthritis - Joint pain and swelling 5
• Peripheral neuropathy - Sensory or sensorimotor symptoms 5
• Abdominal pain - If gastrointestinal involvement 5

Physical Examination Approach

When examining a patient with suspected leukocytoclastic vasculitis:

1. Skin examination:

   • Carefully inspect lower extremities, especially the shins
   • Document distribution, morphology, and extent of lesions
   • Note any necrosis, ulceration, or bullae formation which indicate more severe disease

2. Vascular examination:

   • Check peripheral pulses
   • Look for bruits (particularly in axillary regions) 6

3. Neurological examination:

   • Assess for sensory deficits, paresthesias, numbness which may indicate peripheral nerve involvement 5
   • Look for motor weakness if more severe neuropathy is present

4. Joint examination:

   • Check for tenderness, swelling, or reduced range of motion

Diagnostic Considerations

The diagnosis of leukocytoclastic vasculitis requires:

• Skin biopsy showing characteristic histopathological findings:

  • Neutrophilic infiltrate
  • Fibrinoid necrosis
  • Nuclear fragmentation ("leukocytoclasia")
  • Extravasation of erythrocytes 1

• Laboratory workup to determine if skin-limited or systemic:

  • Complete blood count with differential
  • Renal function tests and urinalysis
  • Serological tests for hepatitis B and C
  • Autoantibody testing (ANA, ANCA)
  • Complement levels
  • IgA levels 1

Clinical Pearls

• Lesions typically appear 7-10 days after exposure to a triggering medication or infection 3
• Up to 50% of cases have no identifiable cause (idiopathic) 3
• The presence of neurological symptoms (neuropathy/mononeuritis multiplex) suggests severe vasculitic involvement 5
• Bullous lesions are uncommon and represent a more severe variant 3

Pitfalls to Avoid

• Don't miss systemic involvement - always perform a thorough review of systems
• Don't confuse with other causes of purpura (thrombocytopenia, coagulopathies)
• Don't overlook medication causes - many drugs can trigger leukocytoclastic vasculitis 4
• Don't miss potential underlying malignancy, infection, or autoimmune disease 2

Early recognition of the characteristic skin findings of leukocytoclastic vasculitis is crucial for prompt diagnosis and management to prevent potential complications from systemic involvement.