Clinical and immunological significance of neopterin measurement in cerebrospinal fluid in patients with febrile convulsions

Neopterin is synthesized mainly by monocytes/macrophages and is considered to be a marker for activation of the cellular immune system. It has been reported that cerebrospinal fluid (CSF) neopterin levels are significantly higher in patients with bacterial meningitis than in those with aseptic meningitis or non-pleocytotic CSF. In this study levels of neopterin and interferon-gamma (IFN-γ) were measured in children with non-pleocytotic CSF. The CSF neopterin levels were significantly higher in patients with typical febrile convulsions (FCs) (15.0±4.5 nmol/l) than in those with pyrexia without convulsions (6.5±2.7 nmol/l) or convulsions without pyrexia, namely, epilepsy (4.8±2.4 nmol/l). The CSF neopterin/serum neopterin ratio (C/S ratio) was also higher in patients with typical FCs (1.54±0.83) than in those with pyrexia without convulsions (0.32±0.18) or convulsions without pyrexia (0.77±0.28). Patients with prolonged FCs tended to have higher CSF neopterin levels than those with typical FCs. There was also a tendency for CSF IFN-γ levels to be higher in patients with FCs than in those with pyrexia without convulsions or convulsions without pyrexia. The results of the present study suggest that some immune activation in the central nervous system (CNS) compartment may be related to the mechanisms of FCs.