Lesional T-cell subset in post-kala-azar dermal leishmaniasis

Abstract

Background. The pathogenesis of post-kala-azar dermal leishmaniasis (PKDL) is ill understood.This study was carried out to find the percentage of T-helper and T-suppressor cells in lesional tissue and their probable role in the pathogenesis of PKDL. Methods. An immunoperoxidase monoclonal antibody technique was used to characterize and quantify the subsets of T lymphocytes in the infiltrate in 25 patients with PKDL. Results. The ratio of T-helper to T-suppressor cells was 0.87 in hypopigmented macules and 0.85 in nodule and/or plaque lesions of PKDL. Conclusions. In this study, there was a definite preponderance of T-suppressor cells over T-helper cells in both types of skin lesions of PKDL. Further studies should be undertaken on larger numbers of patients to compare T-cell subsets both in skin lesions and the circulation, in order to determine the pathogenesis of PKDL. © 2005 The International Society of Dermatology.