2025 – PAGE 405 – NEUROLOGY

ABSENCE SEIZURES

Absence seizures are brief, frequent, generalized (non-focal) seizures that usually begin in school–aged children. Patients often look like they are staring off into space and not paying attention in class.

Seizures

• can often be provoked (or diagnosed) by hyperventilation
• are associated with an EEG showing 3-per-second spike-and-wave discharges (3 Hz spike-and-wave discharges)
• are not associated with an aura or postictal phase.

Treat with ethosuximide or valproic acid.

MNEMONIC: Imagine a kid having an absence seizure in class. The class bully notices him staring off into space. He takes his dirty SOCKS (ethoSUX) and puts them in the kid’s face. When the seizure is over, the kid suddenly smells the SOCKS, jerks back in disgust, and hits his head on the WALL (VALproic acid)!

TONIC-CLONIC SEIZURE

Tonic-clonic seizures are non-focal/generalized seizures that are characterized by an initial tonic phase (extension of the extremities and back) which lasts for less than 30 seconds, and then a clonic phase (jerking). Patient may have incontinence during intermittent periods of atonia. Afterwards, patients are postictal (slow, confused). Treatment options include just about everything (valproic acid, phenytoin, carbamazepine, phenobarbital, and lamotrigine).

NEONATAL SEIZURES

Neonatal seizures can present as brief inactivity, odd facial movements (like lip smacking), or staring. There’s usually NO long-term issue. If it occurs within 24 hours of birth, it’s probably due to asphyxia (look for mild organ dysfunction from hypoxia in other major organs), but you MUST rule out metabolic disease. Can treat with phenobarbital (consider holding off treatment if there is only one event).

INFANTILE SPASMS

Infantile spasms may present in children less than 1 year of age with non-focal seizures involving the flexion and extension of the whole body. Can occur in clusters and may be mistaken for a Moro reflex. They have a strong association with developmentally delayed children and carry a poor prognosis, especially if there was intellectual disability prior to the onset. Diagnose by looking for hypsarrhythmia. (This refers to a characteristic EEG pattern found between infantile spasms.) Treat with ACTH.

PEARLS: LOOK AT THE AGE! The Moro reflex usually disappears by about 4 months of age. This is also very strongly associated with Tuberous Sclerosis.

MNEMONIC: Do you remember the mnemonic of “Tubular bazooka shooting Ash Leafs with DANCING ticks on them?” If not, please review the autosomal dominant mnemonic (in Genetics).

FEBRILE SEIZURE

Simple febrile seizures are non-focal (generalized) seizures that last less than 15 minutes and are associated with a high fever. Typically, these children will not result in more than one seizure in a 24-hour period. Complex febrile seizures are focalized and last greater than 15 minutes. Complex febrile seizures can occur more often than once in a 24-hour period. Simple febrile seizures are much more common than complex febrile seizures. Febrile seizures are usually seen in children 6 months – 6 years of age. Workup should be aimed at the cause of the fever and not at brain imaging. About 30% of these children will have future febrile seizures. The risk of future epilepsy is twice that of the general population (but still VERY low), and kids with complex febrile seizures have a higher chance of developing epilepsy than ones who only have simple febrile seizures.