Comparative evaluation of brain CT and ELISA in the diagnosis of neurocysticercosis.

This study compares the results of cysticercus-specific IgG antibody levels, as measured by enzyme-linked immunosorbent assay (ELISA), with brain CT findings in suspected neurocysticercosis and to assess the clinical significance of ELISA. One hundred twenty-three neurologic patients were examined by both brain CT and ELISA. Sensitivity and specificity of ELISA in confirmed cases were 94% and 91%, respectively. Patients with multiple cysts without enhancement on CT, which were thought to represent viable cysticerci, were positive by ELISA. Those with cysts with enhancement or poorly defined low densities or enhancing nodules, which represented cysticerci on degeneration, were also positive by ELISA. Those with multiple spotty calcifications, which represent cysticerci in the inactive stage, were negative by ELISA. Those with mixed CT findings of the above, which represent the various stages of infection in a patient, were positive by ELISA. Those with only enhancing nodules with surrounding edema, which were thought to be other inflammatory granulomas, were negative by ELISA. If patients with only hydrocephalus on CT are positive by ELISA, they can be confidently diagnosed as having ventricular cysticercosis. The results indicate that ELISA is useful as a complementary diagnostic tool, especially in patients with equivocal CT findings of neurocysticercosis. Provision of etiologic information on a biologic basis was the advantage of this serologic test.