[Evaluation of the polymerase chain reaction for diagnosis of tuberculous meningitis]

Since Shankar et al used polymerase chain reaction (PCR) for detection of Mycobacterium tuberculosis (M. tuberculosis) in cerebrospinal fluid (CSF), there have been numerous reports on PCR assay for diagnosis of tuberculosis meningitis (TBM). The PCR assay have been recognized to be a rapid method for diagnosis of TBM, however there are problems of PCR sensitivity when dealing with CSF samples containing small amount of M. tuberculosis DNA. Comparing direct PCR with nested PCR, we studied on the evaluation of PCR for diagnosis of TBM. In present study the nested PCR were positive in all CSF specimens from 4 patients with TBM, but we could not detect M. tuberculosis DNA by only the direct PCR. Because nested PCR amplification improved the sensitivity and specificity, the nested PCR assay will be necessary for rapid diagnosis of TBM on the clinical laboratory.