Evaluation of polymerase chain reaction [PCR] for rapid diagnosis of clinically suspected tuberculous meningitis

ABSTRACT

Since conventional bacteriological methods rarely detect mycobacterium tuberculosis in cerebrospinal fluid [CSF] and are of limited use in the diagnosis of tuberculous meningitis [TBM], clinical features suggestive of TBM supported by indirect evidence such as CSF examination and computerized tomography [CT] of the head have been used for the early diagnosis of TBM. The aim of this study was to evaluate the efficacy of PCR in the early diagnosis of TBM. Coded CSF samples from 40 patients with TBM and from 40 patients with other neurological disorders were processed. In the absence of a reliable sensitive and specific test of M. tuberculosis in CSF, we used a set established clinical criteria as the gold standard. Accordingly, the patients were divided into highly probable, probable and possible TBM. The samples were decoded only after completion of the laboratory tests. PCR was positive in 4/4, 16/20 and 12/16, patients with highly probable, probable and possible TBM respectively. PCR along with the suggested clinical criteria offers a rapid and fairly accurate diagnosis of TBM