Which neonatal EEG findings are characteristic of herpes simplex virus (HSV) encephalitis?

Updated: Oct 03, 2019
  • Author: Rosalia C Silvestri-Hobson, MD; Chief Editor: Selim R Benbadis, MD  more...
  • Print


Three distinctive patterns are associated with type 1 and type 2 herpes simplex virus (HSV) encephalitis. For pregnant women in many countries, HSV is still the most common (and preventable in neonates by means of cesarean section) genital infection. HSV is easily transmitted to the newborn during vaginal delivery. One type of EEG abnormality consists of continuous, sharply contoured unifocal or multifocal delta activity with a typical asynchronous distribution across several foci (each with a specific rate). Foci are predominantly temporal, frontal, or central in distribution. In older infants, hemispheric, monomorphic slow waves appear interspersed on a low-voltage or suppressed background. They may recur as periodic lateralized epileptiform discharges (PLEDs) within several seconds. Typical electroencephalographic seizures are associated with positive, multifocal sharp waves on a background that is characterized by significant interhemispheric voltage asymmetries and asynchrony.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!