Role of cerebrospinal fluid tau protein levels as a biomarker of brain injury in pediatric status epilepticus.

Background: Various biomarkers have been studied for predicting etiology and outcome in status epilepticus (SE); cerebrospinal fluid (CSF) total tau (t-tau) protein levels is foremost among them. Only handful of studies are available regarding role of t-tau in childhood SE.

Methodology: This prospective study was conducted in a tertiary care center of Northern India in children 6 months -12 years of age. The Cases were patients with convulsive status epilepticus (CSE) whereas Controls were patients without SE and normal CSF. The t-tau levels were done in CSF of both the groups. The outcome was assessed by GOS-E Peds score.

Results: A total of 50 (62% males) cases and 15 (67% males) controls were enrolled in the study. SE was generalized in 78% cases whereas 14% had refractory SE. Most common etiology of CSE was acute symptomatic (52%), followed by prolonged febrile seizure (24%), remote symptomatic group (14%), unknown etiology (8%) and progressive disorder (2%). Case fatality rate was 10%. Poor outcome was seen in 30% cases. Median (IQR) CSF t-tau levels was significantly lower 2.6 × 10 (0.5-9.4 × 10) pg/ml in cases vs 10.6 × 10 (6.0-14.2 × 10) pg/ml in controls ( = 0.004). There was no significant correlation seen between type, duration, etiology and response to antiepileptic drugs of SE with CSF t-tau levels. Also, no significant correlation of poor sensorium, outcome of SE and critical care needs with CSF t-tau levels was noted.

Conclusion: CSF t-tau is not a useful diagnostic or prognostic biomarker in pediatric SE.