It can be difficult to determine whether unusual, paroxysmal behavior represents a seizure or a nonepileptic event. Children with sudden flailing movements or unresponsive staring may, in fact, be experiencing psychogenic events. Other types of pathological spells, such as syncope and migraine, can also be mistaken for epileptic seizures. When epilepsy is incorrectly diagnosed in these patients, unnecessary seizure medication is likely to be prescribed, and correct diagnosis and treatment is delayed. It is also the case that epileptic seizures can be subtle and difficult to recognize. Inattentive staring may be attributed to attention deficit disorder but may, in fact, be due to either absence or complex partial seizures.
An orderly approach to the differential diagnosis of paroxysmal events is the best way to avoid misdiagnosis. A careful, detailed history and physical examination supplemented by an electroencephalogram (EEG) will, in most cases, result in a correct diagnosis.
Epileptic seizures are paroxysmal, abnormal behaviors caused by excessive, hypersynchronous firing of neurons in the brain. Most seizures arise in the cerebral cortex, although subcortical structures can also generate seizures.1,2 The incidence of epilepsy is highest in early childhood and peaks again late in life.3 When epilepsy is attributed to a brain abnormality (eg, mental retardation, cerebral palsy, malformation), it is classified as "symptomatic." Epilepsy is considered "idiopathic" when there is no recognized brain abnormality.4
The risk of recurrence within 2 years after a first-time, unprovoked seizure is approximately 35% to 40%.5 Increased risk of recurrence is associated with factors such as a remote, symptomatic cause (eg, brain injury); abnormal EEG; and seizure during sleep. Treatment with antiepileptic medication reduces the risk of a recurrence after a first seizure, but there is little evidence that treatment prevents the later development of epilepsy.6