Mycobacterium tuberculosis var hominis

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. 

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