Erythematous-edematous-infiltrative plaque on the face: cutaneous angio-lupoid leishmaniasis.

The present report deals with an unusual clinical presentation of cutaneous leishmaniasis occurring in an atopic subject and discusses the possible pathogenetic mechanisms with particular attention to the role of nitric oxide in the immunological control against intracellular parasites. The altered balance between TH1 and TH2, typical of atopy, with consequent production of IL-4, might contribute to the high susceptibility to opportunistic infections and to the unusual clinical presentation. Moreover the laxity of the tissue and the great vascularization may enhance cutaneous expression of the Leishmania infestation, producing new aspects which add to the difficulty of diagnosis.