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Clinical features, evaluation, and diagnosis of neonatal seizures

Author
Renee Shellhaas, MD, MS
Section Editors
Douglas R Nordli, Jr, MD
Joseph A Garcia-Prats, MD
Deputy Editor
April F Eichler, MD, MPH

INTRODUCTION

The occurrence of neonatal seizures may be the first, and perhaps the only, clinical sign of a central nervous system (CNS) disorder in the newborn infant. As such, seizures may indicate the presence of a potentially treatable etiology and should prompt an immediate evaluation to determine cause and to institute etiology-specific therapy. In addition, seizures themselves may require emergent therapy, since they may adversely affect the infant's homeostasis or they can contribute to further brain injury.

The clinical features, evaluation, and diagnosis of neonatal seizures will be reviewed here. The etiology and treatment of neonatal seizures and associated epileptic syndromes are discussed separately. (See "Etiology and prognosis of neonatal seizures" and "Neonatal epilepsy syndromes" and "Treatment of neonatal seizures".)

EPIDEMIOLOGY

Seizures occur more often in the neonatal period than at any other time of life; during this period, they most often occur within the first week of life [1,2]. Reported incidence ranges from 1.5 to 5.5 per 1000 in newborns [2-4] and may be even higher in premature infants [5]. Seizure incidence varies with some specific risk factors. Occurrence increases with decreasing gestational age and birth weight, and with increasing acuity of illness [2,6,7].

ETIOLOGY

Almost all neonatal seizures are "symptomatic" seizures, occurring as a consequence of a specific identifiable etiology (table 1 and table 2) [8-12]. Most etiologies can be broadly categorized as:

Neonatal encephalopathy and hypoxic-ischemic encephalopathy

                      

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Literature review current through: Nov 2016. | This topic last updated: Mon Aug 22 00:00:00 GMT 2016.
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