Which CSF profile is most characteristic of chronic bacterial meningitis?

Which CSF profile is most characteristic of chronic bacterial meningitis?

• A. Neutrophils in CSF with normal glucose
• B. Monocytes in CSF with decreased glucose
• C. Lymphocytes in CSF with decreased glucose
• D. Eosinophils in CSF with normal glucose

Answer: (B)

Chronic meningitis typically produces a mononuclear pleocytosis in the CSF, meaning monocytes (often with lymphocytes) predominate rather than neutrophils. At the same time, glucose in the CSF tends to be decreased because bacteria and activated inflammatory cells consume glucose and the inflammatory process impairs glucose transport. So, a CSF profile showing monocytes with decreased glucose fits chronic bacterial meningitis best. Neutrophils in CSF with normal glucose points toward an acute picture, while a lymphocyte-predominant profile with decreased glucose can occur in TB or fungal meningitis rather than classic chronic bacterial meningitis; eosinophils with normal glucose would suggest parasitic infections rather than bacterial meningitis.

Chronic meningitis typically produces a mononuclear pleocytosis in the CSF, meaning monocytes (often with lymphocytes) predominate rather than neutrophils. At the same time, glucose in the CSF tends to be decreased because bacteria and activated inflammatory cells consume glucose and the inflammatory process impairs glucose transport. So, a CSF profile showing monocytes with decreased glucose fits chronic bacterial meningitis best. Neutrophils in CSF with normal glucose points toward an acute picture, while a lymphocyte-predominant profile with decreased glucose can occur in TB or fungal meningitis rather than classic chronic bacterial meningitis; eosinophils with normal glucose would suggest parasitic infections rather than bacterial meningitis.