Electroclinical Dissociation in Generalized Epilepsy: A Video-EEG Case From Sub-Saharan Africa

Functional neurological symptoms, specifically functional dissociative seizures (FDS), frequently coexist with epilepsy and pose severe diagnostic challenges, particularly in resource-limited settings where video-electroencephalography (video-EEG) access is scarce. Overreliance on interictal or noncausal epileptiform EEG abnormalities without rigorous electroclinical correlation risks misdiagnosis and hazardous escalation of antiseizure medications (ASMs).

We report a 17-year-old male from rural Ethiopia with a 4-year history of genetic generalized epilepsy (GGE) and mild intellectual impairment who presented with persistent, variable left lower limb jerking following a road traffic accident involving the same limb. Video-EEG captured the jerking episodes and demonstrated generalized spike-wave and polyspike-wave discharges (3-4 Hz) that coincided temporally with clinical jerks but lacked electrographic evolution, focal cortical origin, or muscle phase-locking on surface recording. The events occurred exclusively during wakefulness with preserved awareness, no autonomic instability, and no postictal state. Sequential ASM trials (levetiracetam, valproate, clonazepam, and phenobarbital) failed to modulate the jerks. The electroclinical presentation was interpreted as electroclinical dissociation, confirming coexisting generalized epilepsy and FDS. The patient had also undergone posterior fossa decompression for Chiari I malformation 9 days prior, which was excluded as a cause for the motor events based on clinical and radiological stability.

Diagnostic evaluation of FDS should rely on a positive "rule-in" framework as recommended by international guidelines. Even when epileptiform discharges appear on EEG during clinical events, a lack of physiological congruence between electrographic patterns and semiology confirms electroclinical dissociation.