Seizures and epilepsy in children: Classification, etiology, and clinical features
- Angus Wilfong, MD
Angus Wilfong, MD
- Chief of Neurology
- Barrow Neurologic Institute at Phoenix Children's Hospital
Children with epilepsy, particularly infants, differ from adults not only in the clinical manifestations of their seizures, but also in the presence of unique electroencephalogram (EEG) patterns, etiologies, and response to antiseizure drugs. The immature brain, particularly in the neonate and young infant, differs from the adult brain in the basic mechanisms of epileptogenesis and propagation of seizures. It is more prone to seizures, but seizures are more apt to disappear as the child grows.
This topic provides an overview of the classification and etiology of seizures and epilepsy in children. The clinical diagnosis and management of new-onset seizures and epilepsy in children are presented separately. (See "Clinical and laboratory diagnosis of seizures in infants and children" and "Seizures and epilepsy in children: Initial treatment and monitoring".)
Seizure — A seizure represents the clinical expression of abnormal, excessive, synchronous discharges of neurons residing primarily in the cerebral cortex. This abnormal paroxysmal activity is intermittent and usually self-limited, lasting seconds to a few minutes.
On electroencephalography, a seizure ictus is characterized by sustained, abnormal electrical activity that has a relatively discrete beginning and end, and goes through an evolution characterized by changing morphology and amplitude (voltage) of the abnormal discharges. A focal seizure has a restricted regional onset followed by spread to neighboring or remote brain regions. It may spread to deep subcortical regions and evolve to a bilateral tonic-clonic seizure (previously referred to as a secondarily generalized seizure, to differentiate it from seizures that are generalized from the onset) [1-4]. (See "Electroencephalography (EEG) in the diagnosis of seizures and epilepsy".)
When the seizure is prolonged or immediately recurrent without a return of consciousness, this is status epilepticus. (See "Clinical features and complications of status epilepticus in children" and "Management of convulsive status epilepticus in children".)
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- TYPES OF SEIZURES
- Focal (partial) seizures
- Generalized seizures
- Epileptic spasms
- Impact of age
- Structural or metabolic
- - Hippocampal sclerosis
- - Neurodevelopmental lesions
- CLINICAL CHARACTERISTICS
- Clinical behavior during seizures and nonepileptic events
- INFORMATION FOR PATIENTS