A distinctive variant of pernio. Clinical and histopathologic study of nine cases

We describe here nine women who had similar distinctive clinical features that consisted of painful red-to-purple macules, papules, and plaques on the digits, predominantly on the toes. All patients reported that exposure to cold had preceded their symptoms. Histologic study demonstrated a lymphocytic vasculitis, characterized by lymphocytes infiltrating the walls of blood vessels in eight (88%) of nine lesions. This pattern of inflammation is different from the perivascular lymphocytic infiltrate that is common to lupus erythematosus, erythema multiforme, lymphocytic infiltration of the skin (Jessner), and drug eruptions. It also serves to distinguish the disorder from other clinical conditions resembling it, such as cellulitis, herpes simplex infection, and disseminated gonococcemia. To the best of our knowledge, this lymphocytic vasculitis has not been previously described as occurring in pernio. We believe the unique disorder that we are reporting is a common, but infrequently recognized, variant of pernio.