Levels of three inflammation markers, C-reactive protein, serum amyloid A protein and procalcitonin, in the serum and cerebrospinal fluid of patients with meningitis.

The levels of C-reactive protein (CRP) and serum amyloid A protein (SAA) in blood are increased in patients with inflammatory diseases as acute phase proteins. Most of the presently used indicators of inflammation, such as body temperature, white cell count, erythrocyte sedimentation rate or CRP, are non-specific parameters. In contrast, procalcitonin (PCT) has been reported to be selectively induced by severe bacterial infection during the systemic inflammatory response syndrome (SIRS), and also in sepsis or multiorgan dysfunction syndrome. PCT expression is only slightly induced, if at all, by viral infections, autoimmune disorders, neoplastic diseases and trauma of surgical intervention. We measured the concentrations of CRP, SAA and PCT in the sera and cerebrospinal fluid (CSF) of 30 patients with bacterial, viral, or mycotic meningitis, and 12 patients with a noninflammatory central nervous system disease as controls. An extremely high CRP level in CSF of above 100 microg/L was seen in all seven bacterial meningitis patients and in only 10% of the viral meningitis patients. A high SAA level in CSF of greater than 10 microg/L was observed in all of the bacterial meningitis and mycotic meningitis patients, and in 95% of the viral meningitis patients. Among those with bacterial meningitis, the serum PCT level was more elevated in those with more serious bacterial meningitis. The PCT level in the CSF did not significantly differ among the patients with the three types of meningitis. However, the serum PCT level was very high above 0.1 microg/L in all seven bacterial meningitis patients, especially in the clinically serious cases.