Laboratory diagnosis of human neurocysticercosis: double-blind comparison of enzyme-linked immunosorbent assay and electroimmunotransfer blot assay.

Neurocysticercosis is a common disease in underdeveloped countries. Its diagnosis is based on clinical, imaging (tomography or magnetic resonance), epidemiological, and laboratory data. Several methods based on the detection of antibodies against cysticerci in cerebrospinal fluid or serum have been tested. Among them, an enzyme-linked immunosorbent assay (ELISA) based on the use of a crude parasite antigen has been used by the laboratory network of cysticercosis in Mexico, which has given support to clinicians for up to 7 years. A Taenia solium-specific glycoprotein-based electroimmunotransfer blot (EITB) assay was reported to be highly sensitive and specific for this purpose. In order to compare both techniques, we studied 100 neurocysticercosis patients and 70 neurological noncysticercosis controls and searched for specific antibodies in paired samples of serum and cerebrospinal fluid using both techniques. We found that the EITB assay is more sensitive than the ELISA, especially when serum is being tested. Both techniques are more sensitive in cases with multiple living cysts than in cases with single cysts or calcified lesions. No global differences among cases with parasites located in different parts of the central nervous system were found. In the patients with cysts within the parenchyma, the sensitivity of the EITB assay was higher with serum than with cerebrospinal fluid. The immunodominant bands were found to be the same as those previously reported, i.e., GP-39 to -42, GP-24, and GP-13. Based on these results, we suggest the use of the EITB assay in routine diagnosis of cysticercosis for clinical cases.