Tuberculous meningitis

Mycobacterium tuberculosis var. hominis is the primary cause of tuberculous meningitis. Tuberculous meningitis may exist in the absence of disease in the lung or extrapulmonary sites. Upon initial examination, CSF usually contains 100 to 1,000 WBC/mm3, which may be 75% to 80% polymorphonuclear cells. Over time, the pattern of WBCs in the CSF will shift to lymphocytes and monocytes. 

Normal CSF has a characteristic composition in terms of protein and glucose content, as well as cell count. Table 67-2 lists CSF findings observed in the absence of infection, as well as in patients with bacterial, viral, fungal, and tuberculous meningitis. 

Tuberculous meningitis CSF culture, PCR evaluation (preferred), and acid-fast stain... 

The use of glucocorticoids for tuberculous meningitis remains controversial. The administration of steroids such as oral prednisone, 60 to 80 mg/ day (1 to 2 mg/kg/day in children), or 0.2 mg/kg/day of IV dexametha-sone, tapered over 4 to 8 weeks, improves neurologic sequelae and survival in adults and decrease mortality, long-term neurologic complications, and permanent sequelae in children. 

IgM is frequently detected in the CSF of patients with trypanosomiasis, tuberculous meningitis, Staphlococcus meningitis and in patients with Burkitt s lymphoma with CNS involvement and could very well be of diagnostic significance. 

Rifampicin is the most effective drag for treating pulmonary and nonpulmonary forms of tuberculosis, including tuberculous meningitis. It should always be used in combination with other drags. Synonyms of this drag are rifadin, rimactan, rifapiam, rimactazide and others. 

Miscellaneous Tuberculous meningitis with subarachnoid block or impending block when accompanied by appropriate antituberculous chemotherapy in trichinosis with neurologic or myocardial involvement. 

Tuberculous meningitis—clinical manifestation is completely different, but otherwise the differentiation is more feasible using biochemical rather than cytological parameters. Sporadically, the agent is detected by staining for acid-fast... 

Extrapuhnonary cryptococcosis including meningitis Disseminated non-tuberculous mycobacteria infection Progressive multifocal leukoencephalopathy (PML)... 

Isoniazid does not bind to serum proteins it diffuses readily into all body fluids and cells, including the caseous tuberculous lesions. The drug is detectable in significant quantities in pleural and ascitic fluids, as well as in saliva and skin. The concentrations in the central nervous system (CNS) and cerebrospinal fluid are generally about 20% of plasma levels but may reach close to 100% in the presence of meningeal inflammation. 

Glucocorticoids are also used in the treatment of a number of HIV-related disorders, including Pneumocystis carinii pneumonia, demyelinating peripheral neuropathies, tuberculous meningitis, and nephropathy. Glucocorticoids are used as adjunctive therapy in Pneumo cystitis carinii pneumonia to decrease the inflammatory response and allow time for antimicrobial agents to exert their effects. In patients who are immunocompromised because of HIV infection, adjunctive steroids may be less beneficial in promoting survival. 

Neurology Lumbago, sciatica, cervicobrachial neuralgia and other painful radiculopathies selected cases of inflammatory disorders such as tuberculous meningitis and multiple sclerosis. 

Ethambutol hydrochloride, 15-25 mg/kg, is usually given as a single daily dose in combination with isoniazid or rifampin. The higher dose is recommended for treatment of tuberculous meningitis. The dose of ethambutol is 50 mg/kg when a twice-weekly dosing schedule is used. 

Neurologic disease Decreased inflammation and immunosuppression Tuberculous meningitis, multiple sclerosis, myasthenia gravis... 

Ethambutol [e THAM byoo tole] is bacteriostatic and specific for most strains of M- tuberculosis and M- kansasii. Resistance is not a serious problem if the drug is employed with other antituberculous agents. Ethambutol can be used in combination with pyrazinamide, isoniazid, and rifampin to treat tuberculosis. Absorbed on oral administration, ethambutol is well distributed throughout the body. Penetration into the central nervous system (CNS) is therapeutically adequate in tuberculous meningitis. Both parent drug and metabolites are excreted by glomerular filtration and tubular secretion. The most important adverse effect is optic neuritis, which results in... 

CSF protein is usually raised above 1 g/L in bacterial, tuberculous and cryptococcal meningitis and above 0.5 g/L in viral meningitis. 

Tuberculous Meningitis and Extrapulmonary Disease In general, INH, pyrazinamide, ethionamide, and cycloserine penetrate the cerebrospinal fluid readily. Patients with CNS TB are often treated for longer periods (9 to 12 months). Extrapulmonary TB of the soft tissues can be treated with conventional regimens. TB of the bone is typically treated for 9 months, occasionally with surgical debridement. 

There have been two reports of tuberculous meningitis after BCG immunization in immunocompetent individuals, in two French children aged 4.5 and 5 years (40) and in a 22-year-old woman from Cambridge, UK (41). 

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