Which CSF profile is most consistent with bacterial meningitis?

Which CSF profile is most consistent with bacterial meningitis?

• A. Opening pressure > 300 mmH2O; WBC > 1000/µL; glucose < 40 mg/dL
• B. Opening pressure < 300 mmH2O; WBC < 1000/µL; glucose > 40 mg/dL
• C. Opening pressure > 300 mmH2O; WBC < 1000/µL; glucose > 60 mg/dL
• D. Opening pressure < 150 mmH2O; WBC > 5000/µL; glucose < 20 mg/dL

Answer: (A)

Bacterial meningitis drives a strong neutrophilic inflammatory response in the CSF and consumes glucose, all while raising intracranial pressure. The classic CSF pattern reflects these changes: opening pressure is markedly elevated, the white blood cell count is high (typically more than 1000 cells per microliter) with neutrophil predominance, and the glucose level is low (often below 40 mg/dL). This combination is exactly what is described by opening pressure greater than 300 mmH2O, WBC greater than 1000/µL, and glucose less than 40 mg/dL, making it the best fit for bacterial meningitis. The other profiles lack one or more of these hallmark features: viral meningitis tends to have a lower WBC count with lymphocytic predominance and normal glucose, while extremely low glucose with very high WBC but normal pressure is less typical for bacterial meningitis.

Bacterial meningitis drives a strong neutrophilic inflammatory response in the CSF and consumes glucose, all while raising intracranial pressure. The classic CSF pattern reflects these changes: opening pressure is markedly elevated, the white blood cell count is high (typically more than 1000 cells per microliter) with neutrophil predominance, and the glucose level is low (often below 40 mg/dL). This combination is exactly what is described by opening pressure greater than 300 mmH2O, WBC greater than 1000/µL, and glucose less than 40 mg/dL, making it the best fit for bacterial meningitis.

The other profiles lack one or more of these hallmark features: viral meningitis tends to have a lower WBC count with lymphocytic predominance and normal glucose, while extremely low glucose with very high WBC but normal pressure is less typical for bacterial meningitis.