For investigation of CNS infection, please send four routine sterile containers with CSF, labelled in sequential order of collection. Send container 1 and 3 to microbiology for cell counts and culture and send container 2 to virology (for PCR) and container 4 to biochemistry (for protein and glucose +/- xanthochromia). Ensure a paired serum glucose is also sent to allow interpretation of the CSF glucose.

Glucose result should be interpreted with reference to simultaneous blood glucose level. Glucose levels in CSF are typically approximately 2/3 of the plasma glucose level.