Diagnosis of tuberculous meningitis by ELISA test

Detection of IgG antibodies to Mycobacterium tuberculosis H37 Ra antigen in cerebrospinal fluid (CSF), by ELISA test appears to be highly sensitive. In 90 per cent (18/20) of proven cases of tuberculous meningitis (TBM), antibodies were present in CSF; in 75 per cent (15/20) antibodies were also present in the sera. In the patients clinically suspected to have TBM, antibodies in CSF and sera were present in 87.5 per cent (42/48) and 70.8 per cent (34/48) respectively, whereas in the control group antibodies were present in only one serum sample and in none of the CSF samples. The results indicate that ELISA test using sonicated M. tuberculosis H37 Ra as antigen is a sensitive and specific test for diagnosis of TBM.