Determination of the phosphorylated neurofilament subunit NF-H (pNF-H) in cerebro-spinal fluid as biomarker in acute traumatic spinal cord injuries / Dozarea neurofilamentelor fosforilate (subunitatea pNF-H) ȋn LCR ca biomarker ȋn traumatismul vertebro-medular acut

Study objective. The objective of this study was to measure the phosphorylated neurofilament subunit NF-H (pNF-H) in cerebro-spinal fluid of patients with spinal cord injury and to determine the correlation between the pNF-H levels and the severity of the injury. Materials and methods. The study included 15 subjects with acute traumatic spinal cord injury: eight patients with complete spinal cord injury (SCI) and seven patients with incomplete SCI. All patients were classified according to the American Spinal Injury Association impairment scale (ASIA) and all patients underwent surgery during the first 24 hours (decompression, stabilization). We measured daily the heavy phosphorylated neurofilament subunit (pNF-H) concentration by sandwich ELISA test in CSF in all patients and we correlated the values of pNF-H with the clinical evolution. Results. For all patients with SCI pNF-H was detectable in CSF samples and the values were different in the cases of complete SCI toward the cases of incomplete SCI and the cerebro-spinal pNF-H level was more elevated in cases of complete SCI. The level of CSF pNF-H was ten to a hundred times higher in complete SCI than the level of CSF pNF-H in cases with incomplete SCI, where the level of this biomarker was close to normal. The patients with a favorable neurological evolution after treatment had a specific pattern of daily values of pNF-H: a sudden increase up to a maximum value then a progressive decrease until normal. The maximum values were different in each case, from 10 times up to 170 times higher than the normal. Conclusion. The phosphorylated form of the high-molecular-weight neurofilament subunit NF-H (pNF-H) in cerebro-spinal fluid can be a specific biomarker for spinal cord injury and it can distinguish the severity of SCI. pNF-H is a predictive biomarker because of its values pattern can show the reducing or stopping of the secondary lesion and the favorable result.