Which condition is associated with an increased CSF total protein and a decreased CSF glucose level?

Bacterial meningitis is characterized by an elevated total protein concentration in the cerebrospinal fluid (CSF) and a decreased glucose level. This is due to the inflammatory processes that occur when bacteria invade the central nervous system. The presence of bacteria triggers an immune response, resulting in an influx of white blood cells, primarily neutrophils, to the site of infection. This immune response contributes to increased levels of proteins in the CSF as the blood-brain barrier becomes more permeable.

Additionally, a decreased glucose level in the CSF occurs because the bacteria consume glucose for energy and the infection leads to increased metabolic activity. The CSF glucose levels are monitored as part of differentiating various types of meningitis, with bacterial meningitis consistently showing this specific profile of elevated proteins and reduced glucose.

In contrast, conditions like subarachnoid hemorrhage may show elevated protein levels but typically maintain glucose levels, while traumatic taps can alter protein levels due to contamination from blood. Multiple sclerosis often presents with normal glucose levels and elevated protein, but not to the extent seen in bacterial meningitis. Thus, the distinct combination of increased total protein and decreased glucose strongly indicates bacterial meningitis.