Evaluation of enzyme linked immunosorbent--assay for the detection of anticysticercus antibodies in cerebrospinal fluid from patients with neurocysticercosis.

Enzyme linked Immunosorbent Assay (ELISA) was done for the detection of antibodies to Cysticercus cellulosae in 135 cerebrospinal fluid (CSF) and 152 serum samples from patients suspected clinically of neurocysticercosis (NC), neurological disorders other than NC and controls by the use of crude cyst extract antigen. This assay was compared with the standard technique of indirect haemagglutination test (IHA). The results of the two techniques were matched with retrospective analysis of proven diagnosis of these patients. ELISA and IHA was found to be positive respectively in 88 and 84 percent of CSF and 92 and 87.2 percent of serum samples from proven NC patients. The IHA technique was found to be absolutely specific for the detection of antibodies in CSF samples while cross reactions were observed with ELISA technique in CSF from 5 patients, one each suffering from disappearing CT scan lesion, tubercular meningitis (culture negative), chronic meningitis, benign intracranial hypertension and non compressive myelopathy. However possibility of neurocysticercosis cannot be absolutely ruled out in such patients. Both the techniques were found to be highly non specific for the detection of antibodies in serum samples. The study suggests that either of the two techniques may be used for the detection of antibodies in CSF samples from clinically suspected NC patients with high degree of sensitivity and specificity.