Serial study of the immune response of an individual with exacerbated simple cutaneous leishmaniasis.

The immunological responses of a patient with exacerbated cutaneous leishmaniasis, measured during the course of the disease, are described. Except for skin lesions the patient was healthy and showed no signs of immunosuppression. Three immunological parameters were measured: specific lymphocyte proliferation (LPA), monocyte effector activity (MEA), and antibody levels. LPA was positive early in the course of the disease, became negative as the lesions enlarged, and was positive again as the lesions healed 28 weeks after initiation of the study. In the MEA test, in which the mononuclear cells of the patient were incubated in the presence of Leishmania major promastigotes in a 3-day assay, the number of amastigotes per 100 monocytes remained constant until week 28 and then decreased significantly. Antibody levels remained elevated until week 28 and then decreased to background levels. The results indicate that the cell-mediated immune response parallels the course of the disease while circulating antibodies show an inverse relationship.