Pseudopseudoseizures: Conditions That May Mimic Psychogenic Non-Epileptic Seizures

BackgroundVideo electroencephalography (vEEG) has proven to be a valuable tool in the differentiation of pseudoseizures or psychogenic non-epileptic seizures (PNES) from epileptic seizures. Clinicians should, however, be aware of a number of conditions that may be misdiagnosed as pseudoseizures.ObjectiveTo review a number of somatic conditions that can present with disturbances of consciousness and unusual motor activity without epileptiform findings on vEEG.MethodWe report a case of a young woman who presented with a number of neuropsychiatric symptoms, including episodic posturing and rhythmic movements. The absence of epileptiform findings on vEEG resulted in a diagnosis of conversion disorder with pseudoseizures. She was ultimately diagnosed with N-methyl-D-aspartate (NMDA) receptor autoimmune encephalitis (AIE) secondary to an ovarian tumor. AIE and other potential mimics of pseudoseizures are discussed.ResultsA number of somatic conditions can present with symptoms that may be misinterpreted as pseudoseizure.