Evaluation of a 200-kDa amastigote-specific antigen of L-donovani by enzyme-linked immunosorbent assay (ELISA) for the diagnosis of visceral leishmaniasis

A purified 200-kDa antigenic fraction from Leishmania donovani axenic amast igotes was evaluated by ELISA for the detection of antibody response in vis ceral leishmaniasis (VL) patients, post kala-azar dermal leishmaniasis (PKD L) patients and controls, for the diagnosis of visceral leishmaniasis. A po sitive antibody response to the 200-kDa amastigote fraction and to Leishman ia amastigote soluble antigen (LASA) was found in 29 (96.6%) and 30 ((100%) confirmed VL patients, respectively, by the use of ELISA. However, only 1 (10%) out of 10 PKDL patients had detectable antibody response to 200-kDa f raction while all the 10 (100%) PKDL patients exhibited an immune response to LASA. Therefore, use of the 200-kDa antigenic fraction for the detection of antibody response in an ELISA follow-up (post treatment) of VL patients may have prognostic significance, and it may also be useful for differenti ating active VL and PKDL.