ABSTRACT
The skin lesions shown here developed 1 week into an upper respiratory tract infection in a 55-year-old woman. What are these lesions called?
a. Erythema nodosum b. Erythema multiforme c. Erythema infectiosum d. Erythema migrans e. Necrolytic migratory erythema
• This acute, self-limited phenomenon is characterized by “iris” or “target” lesions
• Erythema multiforme is part of the spectrum of conditions, including Stevens-Johnson syndrome (SJS) and, most severely, toxic epidermal necrolysis (TEN)
• It may be associated with infections, including Mycoplasma pneumoniae, Yersinia enterocolitica, and viral infections, especially herpes simplex
• Drug associations include sulfonamides, penicillins, phenylbutazone, barbiturates, phenytoin and other anticonvulsants
• Erythema multiforme is associated less commonly with underlying connective tissue diseases or malignancies
• The differential diagnosis is multiple and includes tinea corporis, urticaria, pityriasis rosea, dermatitis herpetiformis, pemphigus, pemphigoid, lichen planus, and systemic lupus erythematosus
• Treatment of mild cases involves removing offending agents, careful observation, and antimicrobials for superinfections
• Severe cases (SJS or TEN) necessitate hospital admission, aggressive fluid replacement, antimicrobials for superinfections, aggressive supportive care, and ophthalmologic and dermatologic consultations
• Corticosteroid use is controversial
