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5119: Electrographic Seizures in Hyperammonemia


The purpose of this research is to determine if silent seizures (electrographic seizures) occur during a hyperammonemic (HA) episode in patients with urea cycle disorders (UCD). Urea cycle disorders lead to accumulation increased ammonia due to problems breaking down protein. The symptoms of UCD may present at birth, childhood or adulthood (milder deficiencies) and are associated with cognitive deficits, changes in behavior, brain swelling and seizures.

Sometime the seizures are not clinically obvious, but can be picked up if a video recording and concurrent EEG (video EEG is used, cVEEG). cVEEG is used in many intensive care units across the country to pick up seizures. We want to determine if having seizures due to HA leads to any adverse cognitive outcomes, and want to use the EEG to identify any changes that may be associated with that.

For Diseases

This study is for all urea cycle disorders.


About this Study

Your participation in the study will last one year. If during that one year you are hospitalized for a hyperammonemic episode, we would like to collect data from that hospitalization. We will collect data from your electroencephalogram (EEG), magnetic resonance imaging (MRI), and any blood tests done during your hospitalization. These are all procedures that are done as part of routine care. After discharge, we will ask you to participate in follow-up EEGs, MRIs, and cognitive testing at one month, 6 months and one year after the hyperammonemic event.

Target Enrollment

To be eligible to participate, the following criteria must be met:

  • Inclusion criteria:
    1. Patients with HA requiring hospitalization
    2. Ages newborn to 21 years at the time of enrollment
    3. Patients admitted or transferred to a hospital that is able to provide cVEEG (concurrent video EEG) access
  • Exclusion Criteria:
    1. Patients with HA who do not require hospitalization
    2. Skin lesions or scalp edema that precludes accurate placement of EEG leads

To Learn More

To learn more about this a study, please contact a participating site.