Immunological study of hydatidosis. I. Evaluation of immunoelectrodiffusion tests and enzyme-linked immunoelectrodiffusion assay (ELIEDA) in human hydatidosis.

The comparative sensitivity, specificity and rapidity of immunoelectrodiffusion (IED) on cellulose acetate membranes and of immunoelectrophoresis (IEP) on agarose gel, were evaluated in the diagnosis of hydatidosis. Pooled crude fluid from several cattle hydatis cysts was used as antigen in tests on 1,750 non-hydatis and 400 hydatis sera obtained from patients with hepatic, pulmonary, splenic, peritoneal and cerebral hydatidosis before and after surgery. Coupled to a specific human reference serum for arc 5, IED shows a specificity comparable to that of IEP but its sensitivity is slightly higher and the amount of antigen needed is very small. The appearance of a typical "gloved finger" pattern in sera from patients with ruptured cysts emphasizes the interest of quick results (3 hours) obtained by this method. In order to increase the sensitivity of IED and to define the class of immunoglobulins involved in the antigen-antibody reaction, we have coupled this method to an enzymatic technique. The immune complexes precipitated by IED were treated with peroxidase-labelled antibodies specific to each class of human immunoglobulins. The specificity of this enzyme-linked immunoelectrodiffusion assay (ELIEDA) permits one to follow the immunologic evolution of hydatidosis and to identify IgM in ruptured hepatic cysts and IgA in pulmonary cysts.