The clinical patterns, etiologies and times of onset of seizures were determined in a retrospective study of 150 newborns with seizures evaluated between 1982-87 in the neonatal intensive care unit at Washington University School of Medicine, Children's Hospital, St. Louis, MO. Subtle seizures in 97 (65%) infants were characterized by eye movements, sucking, lip-smacking, chewing, tonic posturing, pedaling or rowing movements, and/or apneic spells. Other seizure patterns were multifocal clonic (54%), focal clonic, generalized tonic and myoclonic. Of 78% patients with at least one EEG, only 11% had ictal tracings. Hypoxicischemic encephalopathy (HIE) in 65% of the total was the most common cause of seizures in both preterm and term infants and 90% occurred in the first two days. Intracranial hemorrhage accounted for 10% of seizures. Other less common causes were metabolic, developmental defect, infection and drug withdrawal. In those with developmental defects, the onset of seizures was after 7 days of age. [1]
COMMENT. The authors admit that the absence of simultaneous video-EEG monitoring may lead to misinterpretation of the nature of some clinical phenomena regarded as seizures. Subtle seizures reported in more than half of the patients and associated with HIE have an inconsistent or no relationship to EEG seizure discharges [2], and some authorities advise against anticonvulsant therapy unless EEG epileptiform confirmation is obtained (Ped Neur Briefs 1987;1:47-8). Self-resolution of “seizures” cannot be ruled out in a proportion of those apparently responding to anticonvulsant drugs, a therapy not without potential toxicity.