ELISA using intact promastigotes for immunodiagnosis of kala-azar.

The commonly used diagnostic methods for visceral leishmaniasis (kala-azar) have many disadvantages. ELISA appears to be a more easily applied test for diagnosis, follow-up of treatment and epidemiology. The preparation of the ELISA antigen has given rise to difficulties in standardization since these are usually soluble. Intact cultured promastigotes have been used to develop an ELISA which is sensitive and specific while avoiding the extra handling which is a source of variability and lack of reproducibility. When tested on sera from kala-azar patients and patients with other tropical diseases, this ELISA was able to detect specific antibodies at very high serum dilutions. It is thus promising as a screening method applicable in the field.