EEG showing lateralized periodic discharges (LPDs) in a neonate with HSV encephalitis

EEG in a neonate with HSV encephalitis showing right temporal LPDs (formerly called periodic lateralized epileptiform discharges [PLEDs]). The box on the EEG delineates the LPDs. LPDs appear as unliteral spikes or sharp waves that occur at nearly regular intervals. They are often, though not always, associated with seizures (convulsive or nonconvulsive). LPDs are a characteristic finding in HSV encephalitis. However, the finding is nonspecific, as they can be seen in other encephalitides and other types of brain injury.