Abstract
Erythema multiforme (EM) is an acute, self-limited mucocutaneous disease with diverse triggering factors, and the recurrences are quite common. A 24-year old male presented with multiple erythematous, itchy papules and plaques on multiple sites. He has worked in a lithium battery factory and experienced the chemical burn 2 weeks ago. A histopathologic examination on right wrist showed a scattered lymphocytic infiltration, vacuolar degeneration, and necrotic keratinocyte. The final diagnosis was EM after occupational lithium exposure. He was treated by oral methylprednisolone and experienced recurrences after returning to the same workplace after remission. Although the precise pathogenesis is unknown, the pathogenesis of EM by lithium is related to the effect of lithium on immune system, different from other etiologies. To our knowledge, our case is the first report of EM following the chemical burn and occupational lithium exposure. We report this as an interesting case of EM.