Erythema Multiforme Minor

Diagnosis: Erythema Multiforme Minor

Round papules and plaques made up of a slightly darker zone in the center and a pale ring ( target lesions).

Clinical Presentation

Round papules and plaques made up of a slightly darker zone in the center and a pale ring ( target lesions).

Clinical History

Submitted by Alaa Saad. Originally posted September 28, 2010.

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, minor, alaa saad