Evaluation of Intradermal and Serologic Tests for the Diagnosis of Hydatid Disease

Summary Intradermal tests utilizing an aqueous extract of Echinococcus multilocularis cyst material were performed on 104 individuals living in Uruguay for evaluation of the skin test. In this group, 43 individuals had proven hydatid disease and 61 were normal or had non-hydatid diseases. Antigens containing 0.012 to 0.401 mg N/ml were used. Highest specificity was obtained with skin test antigens which contained 0.012 to 0.015 mg N/ml. Sera from 124 individuals were collected in Uruguay. All but four of the skin-test group were included. Each serum was tested by the indirect hemagglutination, bentonite flocculation and latex agglutination tests. None of the sera in the non-hydatid group reacted in the hemagglutination test and only a few reacted in the bentonite and latex tests. The sensitivity of the serologic tests in patients infected with E. granulosus varied from 82% for serum from individuals with liver cysts to 33–50% for serum from patients with lung cysts.