Erythema nodosum

Overview

• inflammation of subcutaneous fat
• typically causes tender, erythematous, nodular lesions
• usually occurs over shins, may also occur elsewhere (e.g. forearms, thighs)
• usually resolves within 6 weeks
• lesions heal without scarring

Causes

• infection
  • streptococci
  • tuberculosis
  • brucellosis
• systemic disease
  • sarcoidosis
  • inflammatory bowel disease
  • Behcet's
• malignancy/lymphoma
• drugs
  • penicillins
  • sulphonamides
  • combined oral contraceptive pill
• pregnancy