IMPAIRED PRODUCTION OF CYTOKINES IN A CASE OF HUMAN LEISHMANIASIS

A patient presented with the unique clinical picture of diffuse cutane ous and mucosal leishmaniasis caused by Leishmania tropica. Elevated s erum levels of several cytokines including interleukin OL) 2, interfer on gamma (IFN-gamma), and tumor necrosis factor alpha were found. All cytokine levels returned to normal during therapy. No IL-10 or IL-4 le vels were detectable. In whole blood cultures, induction of IFN-gamma by lipopolysaccharide (LPS) was completely negative, even after therap y. Concanavalin A (Con Al-induced release of IFN-gamma, like Con A-ind uced release of the other cytokines, was only initially impaired but r eturned to normal during therapy. Induction of the other cytokines by LPS was never impaired. The low expression of human leukocyte antigen DR on monocytes increased during IFN-gamma therapy but dropped when IF N-gamma treatment was ceased, We conclude that in this patient one or more of the routes of IFN-gamma production was impaired, thus resultin g in insufficient IFN-gamma production in the infected lesions (althou gh IFN-gamma was systemically present).