Efficiency of polymerase chain reaction for the diagnosis of tuberculous meningitis.

The early diagnosis of tuberculous meningitis (TBM) is very important. In this study, the efficiency of the polymerase chain reaction (PCR), one of the most reliable and sensitive DNA-based assays, was compared with conventional methods (acid-fast microscopy and culture) for the detection of M. tuberculosis in cerebrospinal fluid(CSF) specimens from patients suspected of TBM. Of the 29 CSF specimens from highly-probable TBM patients (based on clinical features), 25 were positive by PCR (86.2%), whereas only one of 29 was acid-fast microscopy (AFM) positive (3.4%), and 5 out of 29 were culture-positive (17.2%). No positive results were found by AFM, culture or PCR in the non-tuberculous control group. The results of this study indicate that the application of PCR should be extremely useful in the diagnosis of TBM.