True Epilepsy Unmasked in a Case of Apparent Conversion Disorder

Abstract

Sir: The prevalence of psychogenic nonepileptic seizures is estimated to be between 2 and 33 per 100,000 persons.1 We describe a patient in whom a difficult case of apparent conversion but true epilepsy was unmasked by video-electroencephalogram (video-EEG) monitoring. Case report. Ms. A, a 40-year-old white woman, presented to the neurology clinic with a 2-year history of intermittent spells of disorientation and memory loss. She described these spells as a wavelike sensation starting in her stomach and rising up into her chest, after which she would “blank out” for about a minute or so and then for the next 15 to 20 minutes would ask questions like “Where am I?” “What day is it?” “Am I married?” and “Do I have children?” During these periods, she gradually became more responsive and eventually would become increasingly responsive until the disorientation abated completely. Most of these episodes would occur in her house in the presence of her husband and occasionally in front of her children. She would have no recollection of the event. At no point during these episodes would she lose consciousness or have fecal or urinary incontinence or tongue biting. She denied seeing an aura or any knowledge of exacerbating or relieving factors. These spells could occur as frequently as 10 times in a month, but sometimes a couple of weeks would pass without any episode. Since her first spell 2 years before the admission described in the current report, she had been seen by her primary care physician, neurologist, psychiatrist, and psychologist several times. Occasional complete neurologic examinations revealed no focal findings. Results of a computed tomography scan and magnetic resonance imaging of the head as well as an EEG showed no evidence of intracranial pathology or any epileptogenic activity. EEG testing was repeated several times over the 2-year period and revealed no seizure activity. Her general blood chemistry findings and thyroid profile had also been within normal limits. There was no history of head trauma, febrile seizures, meningitis, or encephalitis and no family history of seizures. Substance use history was nonsignificant. Her medical history was significant for hypertension, which was under good control with amlodipine, 5 mg once daily. She had also been diagnosed with depression for the same period of time and had undergone a trial of venlafaxine, which produced minimal benefits. At the present admission, the depression was under fair control with paroxetine, 60 mg daily. On presentation to our clinic, Ms. A was admitted for video-EEG monitoring, which recorded 1 of her spells. When correlated with the EEG findings, the video-EEG findings revealed left hemispheric slowing with an epileptiform discharge that gradually spread to the bilateral hemispheres. She was then started on lamotrigine treatment for seizure prevention, which led to significant improvement within a few weeks. Around 10% to 20% of patients are found to have both epilepsy and psychogenic nonepileptic seizures.2 Although video-EEG is not widely accepted by psychiatrists, it is considered to be a standard of care for making a diagnosis of psychogenic nonepileptic seizures.2 Obtaining a definite diagnosis and separating seizure disorder from psychiatric disorder is critical, as the treatment for each is different and an early intervention for seizure disorder is essential.3 Failure to treat a true seizure disorder can lead to devastating physical and psychological complications.