There is evidence of a link between transient hyperammonemia (THA) seizures and generalized convulsive seizures (GCS), utilizing video-electroencephalography (vEEG) monitoring, according to a recent study. In a prospective cohort (n=78), researchers screened all consented adults (>18 years) admitted to the epilepsy monitoring unit. Ammonia was checked at baseline, within 60 minutes of the event and 24 hours after event (whenever possible). Patients were grouped in GCS, psychogenic nonepileptic seizures with convulsions (PNES-C), or focal seizures (FS) based on vEEG. They found:

• Of total patients enrolled, 13 had GCS, 8 had FS, and 9 had PNES-C.

• The groups differed with regard to gender and baseline ammonia, but not age.

• The change in ammonia postictally from baseline was significantly different among the 3 groups.

• The area under the receiver operator characteristic (ROC) curve for postictal ammonia to distinguish GCS from other groups was 0.88, suggesting ammonia to be a good test for differentiating epileptic GCS from other events.

Citation: Albadareen R, Gronseth G, Landazuri P, He J, Hammond N, Uysal U. Postictal ammonia as a biomarker for electrographic convulsive seizures: A prospective study. [Published online ahead of print June 1, 2016]. Epilepsia. doi:10.1111/epi.13426.