The Distribution and Aetiology of Diffuse Cutaneous Leishmaniasis in the New World

Abstract

Diffuse cutaneous leishmaniasis (DCL) is an unusual manifestation of cutaneous leishmaniasis in which the skin lesions do not ulcerate, but grow and proliferate as nodules and plaques which slowly but relentlessly spread to cover the entire body, with the exception of the scalp, axillae, inguinal fold, palms of the hands and soles of the feet. It was demonstrated simultaneously but independently in the highlands of Africa [1] and in Venezuela [2], that the condition involves the failure of the patient to elaborate a cell-mediated immune response to the parasite antigen. Apparently there also is a parasite influence involved in this disease manifestation, in that not all species or subspecies of Leishmania which produce cutaneous leishmaniasis produce DCL. To date, to the best of our knowledge, all parasites which have been identified by molecular biology methodologies have been either L. aethiopica in the Old World, or one of the members of the L. mexicana complex in the New World [3].