Neurofilament light chains in serum and cerebrospinal fluid and status of blood-CSF barrier in the selected neurological diseases
Abstract
Aim: The aim of this study was to assess the relationship between blood-CSF barrier permeability evaluated by the albumin quotient (Q(alb)) and levels of neurofilament light chains (NFL) in serum and cerebrospinal fluid (CSF) in several groups of neurological patients with a different degree of the impairment of blood-CSF barrier. Materials and methods: The total number of 137 participants included 50 patients with multiple sclerosis with the inclusion of clinically isolated syndrome, 24 patients with Alzheimer's disease, 17 patients with aseptic neuroinfections, 36 patients with various non-inflammatory neurological diseases and 10 symptomatic controls.
Serum and CSF NFL levels were determined by the ELISA method. Serum and CSF albumin levels were tested by immunonephelometry.
Q(alb) was calculated as a ratio of CSF/serum albumin levels. Results: No positive correlations between serum NFL levels and Q(alb) values were found in the tested patients' groups.
CSF NFL levels were positively cor related with Q(alb) values in patients with neuroinfections and in patients with non-inflammatory neurological diseases. A positive correlation between serum NFL levels and those in CSF was found in patients with aseptic neuroinfections even when patients were evaluated as a whole.
Conclusions: Serum NFL levels do not seem to be directly influenced by blood-CSF barrier permeability asses sed by Q(alb) in neurodegenerative diseases and neuroinfections. On the contrary, the relationship between CSF NFL levels and Q(alb) may be affected by the characteristics of the neuropathological changes in individual neurological diseases.