Dr. Murai Éva szerk.: Parasitologia Hungarica 11. (Budapest, 1978)

principle of coupling antigen to sepharose beads which serve as the antigen substrate. In 1975, DEELDER and STREEFKERK extended the usefulness of the test by combining the principle of the ELISA test with the use of beads, which eliminates the need for a fluorometer and substitutes the development of a color which can be read by the eye. The DASS method merits evaluation for the diagnosis of hydatid infections. Antigens ORIOL et al. (1971) and PAULUZZI and DOTTORINI (1972) have made great strides in purifying and characterizing antigens. These two groups purified lipoprotein antigens (ORIOL et al., 1971) from hydatid fluid which reacted preferentially in diagnostic tests (WILLIAMS et al.

, 1971) but did not have the same sensitivity as the crude antigens. The major breakthrough, however, is the isolation of Band 5 antigen from hydatid fluid by BOUT et al. (1974). This antigen turned out to be similar to antigen A, which ORIOL et al. (1971) isolated and BOMBARDIERI et àl. (1974) found to be the most reactive antigen in agar gel diffusion (AGD). The specific Band 5 antigen is a lipoprotein of molecular weight (MW) 60 000. POZZUOLI et al. (1974) isolated a protein of 400 000 MW and one of 150 000 MW. The 400 000 MW was more immunoreactive than the 150 000 MW protein. With the isolation of the specific Band 5, a specific antiserum has been made. We have used this antiserum, kindly supplied by Dr. CAPRON, and have identified the specific band in our control serum used in DDG. PINON (1976) has used this serum to identify the specific band in CEP. The recent literature is listed on Table 7. Immunoglobulins Using the radioallergosorbent test (RAST), a number of workers have measured significant increases in IgG and IgE. IgE antibody was detectable in some instances in the absence of an IgG response (HULDT et al.

, 1973). With the availability of specific hydatid antigens, the usefulness of the RAST will increase. In spite of the six papers published since 1975 on the use of RAST in hydatid disease, the test has not been fully evaluated. The recent literature is listed in Table 8. The intradermal test (IDT) The IDT is used extensively in the immunological diagnosis of hydatid disease. When compared to other diagnostic procedures, however, the test has a high level of nonspecific results but compares favorably in sensitivity. The ease and comparative sensitivity of the procedure make the technique very attractive, and it is used extensively for epidemiology and diagnosis all over the world. I doubt whether this technique will ever become obsolete. Despite the shortcomings of the test, the IDT can yield more useful data if the antigen is standardized to relatively low nitrogen content (KAGAN et al., 1966; TODOROV et al.

, 1970; WILLIAMS, 1972). In spite of the purity of the IDT antigen produced by boiling hydatid fluid (WILLL4.MS, 1972), SCHANTZ et al. (1975) obtained relatively high levels of nonspecific responses in a study in Peru. Perusal of the reports on the EDT show that most workers inject 0.1 ml of antigen into the skin. In all of our work (KAGAN et al., 1974), we have used 0.05 ml and have not observed the high level of nonspecific results reported in the literature. This point should be evaluated in a special study. The literature on the IDT is listed in Table 9. Conclusion Great strides have been made in the serologic diagnosis of hydatid disease. It is well documented that hydatid disease is caused by several species and physiologically distinct strains of E. granulosus (SMYTH and DAVIES, 1974) and that it differs markedly in clinical manifestations and host responses to infection. This is reflected by the diversity of serologic and immunologic results obtained by workers in different endemic areas of the world. Species-specific components for E. granulosus and E. multilocularis have been identified, and