[Persistent erythema multiforme associated with chronic hepatitis C virus infection. Efficacy of interferon alpha].

Introduction: Persistant erythema multiforme is a rare form of erythema multiforme with subacute typical and atypical lesions that occur during several months. Some cases are associated with chronic viral infection.

Case Report: A 23 year-old man, with a past history of intravenous drug addiction and chronic hepatitis C virus infection, presented persistant erythema multiforme for 18 months. The histopathological picture was those of infectious erythema multiforme and the seric total complement level was low. Two courses of alpha-interferon treatment were quickly efficient on cutaneous lesions, and relapse occurred after discontinuation.

Discussion: In previously reported cases of persistant erythema multiforme, etiologic complementary investigations are not always specified. However, viral infections should be considered. In cases of chronic infection, hepatitis C may induce immune disorders through persistent antigenic stimulation.