erythema multiforme

Diagnosis: erythema multiforme

erythema multiforme

Clinical Presentation

erythema multiforme

Clinical History

Submitted by Ellie Goulding MD. Originally posted January 23, 2017.

Treatment

See case discussion.

Differential Diagnosis

• Stevens-Johnson syndrome/toxic epidermal necrolysis • Urticaria • Drug eruption • Vasculitis • Secondary syphilis • Viral exanthem • Lupus erythematosus • Fixed drug eruption

Key Learnings

• Classic "target" or "iris" lesions with three zones are pathognomonic • Most commonly triggered by HSV infection (>70% of cases) • Drug-induced EM is much less common than historically believed — most drug reactions previously labeled EM are actually SJS • EM minor: skin only, typically acral. EM major: skin + mucosal involvement • Recurrent EM: consider chronic HSV suppression with acyclovir/valacyclovir • Self-limited in most cases (2-4 weeks)

Tags: erythema, multiforme, ellie goulding md