[The diagnosis of tuberculous meningitis using polymerase chain reaction]

The PCR system can detect 10 pg of DNA and 10-50 cfu of M. tuberculosis. The sensitivity and specificity rate of our PCR system about 80 cases of tuberculosis meningitis and 63 cases of nontuberculous meningitis is 85% and 98.4%, respectively. Comparing with the routine mycobacterial examination in 61 cases of tuberculous meningitis, the positive rate of PCR is 86.9%, while the positive rate of routine mycobacterial examination (smear and/or culture) is only 13.1%. In the 53 negative cases of routine mycobacterial examination, the positive rate of PCR can reach 86.8%. The whole detection can be finished within 2 days.