Which CSF laboratory finding is NOT expected in bacterial meningitis?

Which CSF laboratory finding is NOT expected in bacterial meningitis?

• A. Decreased protein
• B. Elevated white blood cell (WBC) count
• C. Cloudy in color
• D. Decreased glucose

Answer: (A)

In bacterial meningitis, CSF changes reflect acute inflammation and bacterial metabolism. You typically see elevated protein from inflammation and disruption of the blood-brain barrier, a high white blood cell count with neutrophil predominance, and a lowered glucose level because bacteria and inflammatory cells consume glucose. The CSF may also look cloudy or turbid due to the high cell and protein content. So a decrease in protein would not fit this pattern and isn’t expected in bacterial meningitis. The other features—elevated WBC count, cloudy appearance, and decreased glucose—are all classic in this setting.

In bacterial meningitis, CSF changes reflect acute inflammation and bacterial metabolism. You typically see elevated protein from inflammation and disruption of the blood-brain barrier, a high white blood cell count with neutrophil predominance, and a lowered glucose level because bacteria and inflammatory cells consume glucose. The CSF may also look cloudy or turbid due to the high cell and protein content. So a decrease in protein would not fit this pattern and isn’t expected in bacterial meningitis. The other features—elevated WBC count, cloudy appearance, and decreased glucose—are all classic in this setting.