Periodic Lateralized Epileptiform Discharges in Infants

Abstract

We reviewed clinical and electroencephalographic data on 2 infants, one with purulent meningo-encephalitis (4 months old, boy) and the other with H. H. syndrome (9 months old, girl), both with periodic lateralized epileptiform discharges (PLEDs) in their electroencephalograms (EEG).
The features of PLEDs in our cases were as follows: 1) they were observed in acute cerebral lesions with generalized convulsions and/or partial convulsions, 2) their appearance was transitory and their duration was two to three days, 3) in the EEG, they were observed at intervals of 0.5-2 seconds and at voltages of 70-100, μV, and consisted of sharp waves, positive spikes, and spike and wave discharges. These PLEDs were found in the disturbed area of the cerebrum in the case of purulent meningo-encephalitis.
By comparing the EEG and CT scans in the case of purulent meningo-encephalitis, it was thought that the causes of PLEDs were brain edema and brain bleeding. Therefore, we suspected that both the separation of cerebral cortex and white matter, and optimum damage to cortex are necessary for the appearance of PLEDs. We indicated that PLEDs were also observed in a process of development in the infants as is in the cases of adults.