Children presenting with a first seizure can be quite distressing for the family and caregivers. When one considers that about 10% of the population will have at least once seizure at some time in their lives and about half will have multiple seizures, the importance of proper assessment is brought into focus.
It is worth noting that the basic definition of Epilepsy includes at least two unprovoked seizures occurring more than 24 hours apart. Accurately making an early assessment can avoid unnecessary treatment of patients unlikely to have a second unprovoked seizure. In many cases extensive workup might not be needed. Decisions about treatment after a single seizure include considerations of the chance of having a second seizure, the consequences of having a second seizure, efficacy of medications in preventing future seizures, and the potential toxicity of antiepileptic drugs (AEDs). The chance of seizure recurrence is one of the most important determinations that will guide treatment decisions.
While one must still deal with probabilities, fortunately, a number of population studies exist that can assist in this determination. As a general rule, after one unprovoked seizures (or more than one within 24 hours), the risk for a recurrent seizure is about 30 - 40%. However, after a second unprovoked seizure (more than 24 hours apart), the risk of subsequent seizures increases dramatically to about 70 - 80%. Most recurrences are within 1 year of the second or third seizure.
In assessing a child with a “first” seizure, the neurologist must also determine whether the patient has actually had multiple and previous seizures. It is common for patients to seek medical care after the first generalized tonic-clonic seizure, but they may not have appreciated the significance of twitches and jerks, nocturnal events and staring spells. A careful history will often determine that many patients with newly diagnosed seizures have actually had previous unrecognized events. This is particularly true in children with complex partial and absence seizures.
The process of making the diagnosis and proper evaluation will need to be based on a detailed history of the event(s) as well as past medical and family history in conjunction a Neurological examination. We will discuss details of a comprehensive neurological evaluation for Epilepsy in future postings.
CONTINUUM: Lifelong Learning in Neurology: February 2016 - Volume 22