Role of Phosphorylated Neurofilament H as a diagnostic and prognostic marker in traumatic brain injury

Abstract Background and purpose One of the main drawbacks in the management of patients with traumatic brain injuries (TBI) is the absence of a widely available and rapid diagnostic test. The objective of our study was to assess whether Phosphorylated Neurofilament H (pNF-H) might provide useful diagnostic information as an indication of axonal injury in the early evaluation of such patients and whether levels of the pNF-H correlated with different clinical variables. Methods A total of 30 patients presenting to the critical care department of Cairo University diagnosed with traumatic brain injury were prospectively studied. Blood samples for pNF-H were assayed on admission and after 7 days. Neurofilament levels correlated with Glasgow coma scale and CT findings on admission and after 7 days. Rankin score at 3 months was used to detect the degree of disability. Results Phosphorylated Neurofilament H levels showed a negative correlation with GCS on admission and after 7 days in traumatic brain injury; hence higher neuromarker levels were associated with lower GCS on admission and after 7 days. There was a negative correlation between neurofilament levels and Marshal CT scores on admission and after 7 days ( r = 0.56.0.4) hence higher neurofilament levels correlated with worse CT findings. Patients who died or had the greatest Rankin 6 and 5 after 3 months had the highest levels of pNF-H on admission and after 7 days. The cut off level of pNF-H to detect death and disability was 35 pg/ml on admission (sensitivity 82%, specificity 78%) and was 11 pg/ml after 7 days (sensitivity87%, and specificity 92%). Conclusion Phosphorylated Neurofilament H can be used as a diagnostic and prognostic marker in patients with TBI as seen by the presence of significant correlations between the marker levels and different clinical and radiological tools.