neurologic disorders
Subacute and Chronic Meningitis
Tuberculous meningitis
 Tuberculosis (TB) are aerobic bacteria that replicate in host cells; thus, control of these bacteria depends largely on T cell-mediated immunity. These bacteria may infect the central nervous system (CNS) during primary or reactivated infection. In high-resource countries, meningitis usually results from reactivated infection. Reactivation may occur in patients treated with immunosuppressants such as tumor necrosis factor (TNF)-alpha antagonists (eg. Meningeal symptoms usually develop over days to a few weeks but may develop much more rapidly or gradually. Characteristically,M. tuberculosiscauses a basilar meningitis that results in 3 complications: Hydrocephalus due to obstruction of the foramina of Luschka and Magendie or the aqueduct of Sylvius Overview of Vasculitis , sometimes causing arterial or venous occlusion and stroke Overview of Neuro-ophthalmologic and Cranial Nerve Disorders , particularly of the 2nd, 7th, and 8th cranial nerves Diagnosis of tuberculous meningitis may be difficult. There may be no evidence of systemic tuberculosis. Inflammation of the basilar meninges, shown by contrast-enhanced CT or MRI, suggests the diagnosis. Characteristically, include Mixed pleocytosis with lymphocytic predominance Low glucose Elevated protein Occasionally, the first CSF abnormality is extremely low glucose. Detecting the causative organism is often difficult because CSF acid-fast staining is < 20% sensitive, even using immunofluorescence techniques. CSF mycobacterial cultures are only about 70% sensitive and require up to 6 weeks. CSF PCR is about 50 to 70% sensitive. An automated rapid nucleic acid amplification test calledXpert MTB/RIFhas been recommended by the World Health Organization (WHO) for the diagnosis of tuberculous meningitis. This test detectsM. tuberculosisDNA and resistance to rifampicin in CSF specimens. Skin testing with controls for anergy or QuantiFERON®-TB Gold testing can document prior exposure toM. tuberculosis; however, results may be negative, particularly in older or immunosuppressed patients. Chest x-rays may show evidence of prior or ongoing infection (in 40 to 50% of cases), and chest CT is positive in up to two thirds of cases. Because tuberculous meningitis has a rapid and destructive course and because diagnostic tests are limited, this infection should be treated based on clinical suspicion. Currently, the WHO recommends treatment with the First-line drugs for TB 