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bioRxiv · 10.1101/184366

Systemic evidence of acute seizure-associated neuronal injury in patients with temporal lobe epilepsy

Kunda, S.·LaFrance-Corey, R. G.·Khadjevand, F.·Worrell, G. A.·Howe, C. L.
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Abstract

Patients with drug refractory temporal lobe epilepsy frequently accumulate cognitive impairment over time, suggesting neuronal loss induced by seizures. We measured serum levels of neuron-specific enolase (NSE), a neuronal injury marker, relative to levels of S100{beta}, a marker of glial injury, at 6 AM, 9 AM, noon, 3 PM, and 6 PM over the course of several days in 7 epilepsy patients and 4 healthy controls. All epilepsy patients exhibited significant deviations in NSE levels through time, and 4 of the epilepsy patients exhibited large sample entropy values and large signal variation metrics for NSE relative to S100{beta}. Controls did not exhibit such changes. Correlation analysis revealed that NSE levels were significantly elevated after clinical seizure events. There was also a highly significant relationship between increased EEG spike frequency and an increase in serum NSE levels measured 24 hours later. The detection of large but transient post-ictal increases in NSE suggests that even self-limited seizures may cause an injury to neurons that underlies cognitive decline in some patients. Post-ictal assessment of serum NSE may serve as a biomarker for measuring the efficacy of future acute neuroprotective strategies in epilepsy patients.

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Kunda, S., LaFrance-Corey, R. G., Khadjevand, F., Worrell, G. A., Howe, C. L.. 2017-09-04. Systemic evidence of acute seizure-associated neuronal injury in patients with temporal lobe epilepsy. https://doi.org/10.1101/184366

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