Serial cerebrospinal fluid neurofilament concentrations in bacterial meningitis

Abstract Neurofilament (NF) is one of the major cytoskeleton proteins of neurons. We investigated the concentrations of the heavy subunit of NF (NF-H) in cerebrospinal fluid (CSF) as biomarkers of neuronal injury in bacterial meningitis. Concentrations of NF-H in CSF of 26 children with bacterial meningitis and in 16 control subjects were measured by ELISA. The CSF NF-H levels were elevated in 22 of the 26 children (85%) with bacterial meningitis. The peak CSF NF-H level occurred at a median period of 10.5 days after onset of illness (range, 1 to 35 days). The peak CSF NF-H levels of the patients with neurological sequelae ( n  = 4) were significantly higher than those without sequelae ( n  = 22) (7.06 vs. 2.46 ng/mL as median, p  = 0.048). There was no significant difference in CSF NF-H levels between patients with and without severe neurological sequelae up to day 14 of illness, but the CSF NF-H levels in patients with sequelae were significantly higher than in those without sequelae after day 14 of illness (2.04 vs. 1.19 ng/mL as median, p  = 0.024). We suggest that neuronal injury occurs in bacterial meningitis regardless of the presence or absence of neurological sequelae.