[1][5] Mycobacterium tuberculosis of the meninges is the cardinal feature and the inflammation is concentrated towards the base of the brain.

[6] When the inflammation is in the brain stem subarachnoid area, cranial nerve roots may be affected.

[3] Diagnosis of TB meningitis is made by analysing cerebrospinal fluid collected by lumbar puncture.

[citation needed] This is a group of tests that use polymerase chain reaction (PCR) to detect mycobacterial nucleic acid.

[16] The fully automated PCR test using the Cepheid GeneXpert system of the Xpert Ultra MTB/RIF has improved sensitivity of up to 77% in persons with HIV and TB meningitis.