Dissociative seizures mimicking epileptic seizures: diagnostic challenges in a case with atypical eye movements

Dissociative seizures (DS), also known as psychogenic non-epileptic seizures (PNES), often mimic epileptic seizures (ES), leading to misdiagnosis, unnecessary anti-seizure medications (ASMs)/ suboptimal use of ASMs, and delays in appropriate care in approximately one-third of patients. Rare presentations, such as episodes resembling oculogyric crisis (OGC), further complicate differentiation. This report highlights the diagnostic challenges of DS with atypical features and emphasises the role of video-electroencephalogram (VEEG) in early differentiation.

We present a 16-year-old male with recurrent episodes of upward eye deviation, non-synchronised limb twitching, and bizarre behaviours, initially misdiagnosed as epilepsy and autoimmune encephalitis. Comprehensive investigations, including normal neuroimaging, absence of epileptiform activity on VEEG, and psychological evaluation revealing moderate depression, supported a diagnosis of DS. The patient showed significant improvement with sertraline and cognitive behavioural therapy.

This case underscores the diagnostic challenges posed by atypical DS presentations and highlights the value of/need for VEEG and psychiatric evaluation in differentiation. Early identification of DS can prevent mismanagement and optimize outcomes.