Serological diagnosis of neurocysticercosis: evaluation of ELISA tests using cyst fluid and other components of Taenia solium cysticerci as antigens.

An ELISA system was developed to assist with the diagnosis of neurocysticercosis. Antigens were prepared from the fluid, the protoscolex and the cyst wall of cysticerci dissected from infected pigs. The fluid antigen was tested both fresh and after freeze-drying and one year's storage. Sera from patients with proven neurocysticercosis were most reactive using the fluid and least reactive using the cyst wall antigens. Freeze-drying and prolonged storage of fluid antigen did not reduce its reactivity and repeated testing of sera with this antigen gave optical density values within 15% of the original value. Using this ELISA system positive results were obtained from all patients with active neurocysticercosis. Sera from patients with calcified cysts were usually non-reactive or marginally reactive to the fluid antigen.