Does CSF antibodies assay help in differentiating neurocysticercosis from tuberculoma?

Introduction: Two common causes of ring/disc enhancing lesions in CT scan or MRI scan of brain are Cysticercosis and tuberculoma. It is often difficult to know the cause in a patient with ring/disc lesions.The gold standard being tissue diagnosis, which is often not done or not practical due to procedural complications and most of these lesions carry a benign course. The present study was undertaken to test the sensitivity and specificity of CSF antibodies in Definitive cases of Neurocysticercosis and Tuberculoma. Materials and Methods: A Cross-sectional descriptive study was conducted with a sample size of 50 patients. The duration of study was for 2 years. Consecutive patients visiting the neurology department with complaints of seizures, headache and focal neurological deficit and their neuroimaging demonstrating a ring/disc enhancing lesions, suggesting either a Cysticercosis or Tuberculoma were included. Patients were subjected to a detail clinical history and examination. Complete hemogram, complete blood chemistry, HIV serology and Neuroimaging either MRI or CT brain were done. Lumbar puncture was done in all patients if there were no contraindications.CSF analysis for antibodies against antigens of cysticercosis and anti-tubercular antibodies were done. Antibody estimation is done by ELISA method. Results: There were 52 patients in the study of which 26 patients were diagnosed as Neurocysticercosis and 11 patients as Tuberculoma. In all 26 patients with Cysticercosis CSF was showing less than 4 cells with normal glucose and protein. Out of 11 patients with tuberculoma only one patient CSF study was abnormal.CSF Elisa for anticysticeral and antitubercular antibodies were done in all patients and were negative in all them. Conclusion: CSF ELISA test for anticysticercal antibody and anti tubercular antibody test has a low sensitivity and is not helpful in the diagnosis of ring enhancing lesions in the brain.