Pre- and postsurgical detection of IgG, IgM, and IgA specific to hydatidosis by ELISA with purified antigen enriched with the 5/B antigen complex.

An enzyme-linked immunoassay (ELISA) using purified 5/B Echinococcus enriched antigen was used to follow IgG, IgM, and IgA antibody levels pre- and posttreatment or surgical removal of hydatid cysts. The sensitivity was 97%, 37.5%, and 54.5%, respectively, and the specificity was 95.7%, 100%, and 98.9%, respectively. All isotypes could be detected 3 years after surgical removal of cysts in patients showing no remaining cyst evidence. This was especially true for IgG, which persisted in 85.2% of the patients. The data indicate that antigen purification improves specificity without affecting sensitivity, although this new antigen offers no advantages in the postsurgical monitoring of the patients.