Serological diagnosis of hydatid disease by enzyme linked immunosorbent assay (ELISA) using partially purified hydatid cyst fluid antigens.

Experimentally, two hydatid cyst fluid (HCF) antigens (antigens 4 and 5) were found to be the most immunogenic antigens in HCF. The two antigens were precipitated together from HCF. This was done by adding 2M phosphotungstic acid and 2M magnesium chloride solutions to clarified HCF while continuously stirring the mixture. The precipitate formed was suspended in physiological saline (P.S.). This antigens' solution was used to coat microtitre plates for indirect ELISA. Indirect ELISA was performed on 180 randomly selected bovine sera. The sensitivity of the test was found to be 98% while the specificity was 70%. The predictive value was 89%. Although the specificity of the test was relatively low, the test using these partially purified antigens was found to be useful because of its high sensitivity.