Cryptogenic new-onset refractory status epilepticus (cNORSE) was associated with strikingly higher neurofilament light chain (NfL) levels in serum and cerebrospinal fluid than etiology-defined status epilepticus (eSE), chronic epilepsy, and healthy controls.
S100B did not meaningfully distinguish cNORSE from comparator groups, suggesting that NfL is the more informative marker of acute neuroaxonal injury in this setting.
NfL rose quickly over the first 3 weeks after onset, supporting the concept that the window to prevent ongoing brain injury may be narrow.
Higher serum NfL was independently associated with worse functional status at discharge, reinforcing its potential prognostic value.
