To highlight the importance of identifying epileptic encephalopathy among patients with Down Syndrome (DS).

Individuals with DS have an increased risk of developing dementia as well as seizures. When patients with DS present with worsening of cognition, it is frequently attributed to the development or progression of dementia. However, when these patients also have seizures, epileptic encephalopathy must be ruled out as it is a treatable condition.

We present a 58-year-old female with DS, dementia and myoclonic seizures. She was admitted to the Epilepsy Monitoring Unit (EMU) for video-EEG monitoring and evaluation of her seizures and cognitive deterioration.

During the patient’s EMU stay, she had periods where cognitive impairment appeared to be more severe, and the EEG showed continuous generalized spike wave discharges during these times. These discharges disappeared upon administration of IV levetiracetam, and cognitive improvement was seen. The video-EEG evaluation was suggestive of epileptic encephalopathy in the setting of a generalized epilepsy. The patient was discharged on higher doses of levetiracetam. There was clear improvement in her cognition and her myoclonic seizures had resolved at a one year follow up visit.

In patients with DS and dementia who also have seizures, epileptic encephalopathy should be kept in mind as a cause of worsening cognition as it is a treatable condition. Intensive video-EEG monitoring is essential to establish the diagnosis of epileptic encephalopathy.