Levamisole and immune response phenomena in cutaneous leishmaniasis.

Levamisole has been successfully used therapeutically in twenty-eight cases of chronic cutaneous leishmaniasis. It is suggested that repeated sandfly bites not initiating a clinical lesion may immunize against later infection by the formation of blocking antibodies to Leishmania tropica or by denying the parasite a locus in which it can become established. Late-appearing lesions in natives of endemic areas should raise the suspicion of impaired immunity from systemic disease such as malignancy.