Chapter 54 - Neonatal seizures and postneonatal epilepsy – causes

Summary

Neonatal seizures are usually considered of epileptic origin, although some may be generated by non-epileptic mechanisms. Neonatal seizures may be classified by clinical features: focal clonic, focal tonic, myoclonic, spasms, generalized tonic and motor automatisms. The main categories of etiological factors of neonatal seizures include hypoxic- ischemic encephalopathy, central nervous system (CNS) infections, structural brain abnormalities, and metabolic disturbances. Early neuroimaging studies, particularly magnetic resonance imaging (MRI) with diffusion imaging, should show acute diffuse abnormalities consistent with hypoxia/ischemia. Some neonatal seizures result from long-standing disorders. These disorders include cerebral dysgenesis, neurocutaneous syndromes, genetic disorders, or very early onset epilepsy in association with well-defined epileptic syndromes. Clinical examination and seizure characterization are initial points of reference in the evaluation of infants suspected of early myoclonic encephalopathy (EME). Benzodiazepines are frequently used as alternative secondline antiepileptic drugs (AEDs), although more often they are given following phenobarbital and in place of phenytoin.