A single, small (< 20 mm), ring or disc shaped contrast enhancing lesion located at the cortical-subcortical junction with minimal or no surrounding edema on computed tomography is the commonest mode of presentation of neurocysticercosis in the Indian subcontinent. Serum samples of 37 patients with these single, small enhancing lesions (SSEL's) and five patients with typical multilesional parenchymal neurocysticercosis were tested by the electro-immunoblot transfer (EITB) assay and the enzyme linked immunosorbent assay (ELISA). EITB was positive in 18 patients (48.64%) and ELISA was positive in 21 patients (56.76%) with SSEL's. On the other hand EITB was positive in all five patients (100%) and ELISA was positive in four patients (80%) with multilesional neurocysticercosis. The low sensitivity of the EITB in the SSEL's is probably linked to an insufficient immune stimulation provided by a single cysticercus cyst.