Disseminated granuloma annulare following erythema multiforme minor.

A 44-year-old woman presented with erythema multiforme minor followed by disseminated granuloma annulare 4 weeks later. The patient was not taking any medication and had no history of herpes simplex infection. Involvement of a delayed-type hypersensitivity reaction in the pathogenesis of these two well known disorders, as suggested by immunological investigations, may explain their concurrence in our patient. The substitution of the erythema multiforme minor lesions by an eruption of disseminated granuloma annulare at the same sites suggests the possibility of a Koebner phenomenon or an isotopic response.