Lymphocyte transformation test: a new method for diagnosis of neurocysticercosis.

Neurocysticercosis (NCC) is the commonest parasitic disease of the central nervous system. Neuroimaging tools are considered gold standard for the diagnosis of NCC, but its availability is restricted in developing countries. So, there is a definite need for reliable immunodiagnostic tool. The aim of the present study was to evaluate cyst fluid antigen-based lymphocyte transformation test (LTT) as a diagnostic tool for NCC. Tissue culture plates (96 wells) were coated with cyst fluid having protein concentration of 20 mug/well. Freshly isolated lymphocytes from 48 symptomatic NCC cases, 39 matched disease controls, and 40 healthy volunteers were seeded at a concentration of 1 x 10(6) cells/well. LTT was performed as per standard guidelines and (3)H-thymidine was used to measure cell proliferation. The cutoff stimulation index (SI) was defined as mean of controls +2 SD. The mean SI of the cell proliferation for NCC cases was significantly higher than controls (5.83 versus 1.29, P < 0.001). The sensitivity and specificity of LTT for diagnosis of NCC were 93.8% and 96.2%, respectively. The study shows that LTT can be used as an immunodiagnostic tool for NCC; however, it needs to be validated in other endemic areas.