Updated: 10/19/2017

Erythema Nodosum

Review Topic
  • A 33-year-old man presents with a 1-week history of a painful rash on his shins. He recently attended a music festival in the desert near California. He reports developing a rash a few days after returning back to New York. He also reports having joint pain throughout his body, particularly his knees and elbows. Physical exam reveals multiple, symmetrically distributed 1-3 cm erythematous and warm subcutaneous nodules on his anterior shins.
  • Clinical definition
    • a panniculitis characterized by painful subcutaneous nodules typically located on pretibial surfaces
  • Epidemiology
    • incidence
      • the most common panniculitis
    • demographics
      • female > male
      • peak incidence between 20-30 years of age
    • risk factors
      • infection
      • autoimmune disease
      • leprosy
  • Pathogenesis
    • some evidence suggests 
      • type IV delayed hypersensitivity response
      • immune complex deposition in venules of connective tissue or subcutaneous fat, causing subcutaneous nodules
  • Associated conditions
    • infection
      • coccidioidomycosis (desert bumps)
      • histoplasmosis
      • tuberculosis
      • streptococcus
      • leprosy
      • Behcet syndrome
      • Sweet syndrome
    • inflammatory bowel disease 
    • sarcoidosis
  • Prognosis
    • erythema nodosum typically resolves spontaneously and fades over 1-2 months
  • Symptoms
    • sudden onset painful symmetric rash
    • often preceded by inflammation/infection
    • may be preceded by prodrome
      • fever, malaise, and fatigue
      • arthralgia
  • Physical exam
    • warm and erythematous subcutaneous nodules that are 1-10 cm in diameter 
      • tender to palpation
    • poorly demarcated margins
    • location
      • typically symmetrically on anterior shins
      • can also affect forearms, thighs, trunk, head, or neck
  • Labs
    • ↑ inflammatory markers
      • erythrocyte sedimentation rate
      • C-reactive protein
  • Biopsy
    • indication
      • only if diagnosis is unclear clinically
  • Histology
    • septal panniculitis without vasculitis
      • septa is thickened and has inflammatory infiltration
  • Scleroderma
  • Granulomas
  • Management approach
    • treat underlying cause
  • Medical
    • nonsteroidal anti-inflammatory drugs (NSAIDs)
      • indication
        • for symptomatic relief as needed
  • Secondary bacterial infection

Please rate topic.

Average 4.2 of 5 Ratings

Thank you for rating! Please vote below and help us build the most advanced adaptive learning platform in medicine

The complexity of this topic is appropriate for?
How important is this topic for board examinations?
How important is this topic for clinical practice?
Topic COMMENTS (0)
Private Note