The concentration of CSF lactate depends largely on production from CNS glycolysis and is independent of blood lactate. Increases in CSF lactate may be due to diverse processes, such as hypoxia of inflamed tissues, cerebral oedema or granulocyte and bacterial metabolism. In most cases of infectious meningitis, however, the CSF production of lactate is apparently a sequelae of, and proportional to, increased numbers of leukocytes.
Differential diagnosis of bacterial and viral causes of meningitis (raised in bacterial).
CSF in fluoride oxalate (grey top)