• CSF:blood glucose ratio is a useful characteristic in differentiating bacterial meningitis from viral meningitis. 
• Normal CSF glucose is at least 2/3 of serum glucose level.
• In bacterial meningitis, CSF:blood glucose ratio is usually <0.4
• Rousseau et al. conducted a study comparing CSF:blood glucose ratio obtained using a bedside glucometer with the laboratory.
• They found the optimal cutoff of CSF:blood glucose ratio using a bedside glucometer is 0.46 compared to 0.44 using the laboratory.
• This proof-of-concept study suggests that a point-of-care glucometer can be used for rapid diagnosis of abnormal CSF:blood glucose ratio in the evaluation of meningitis.

References