1B. Accidental (provoked) seizures
The word “accidental” is probably a mistranslation from Hungarian. In the Hungarian topic list, the word “alkalmi” is used, which translates to “occasional”. “Accidental seizure” is not a thing.
Also, some sources consider “provoked” and “symptomatic” seizures to be the same, but the lecture considers them to be two separate entities.
Provoked seizures
A provoked seizure is one caused by well-defined provoking factors and not by an underlying disorder.
Etiology
- Febrile seizures in childhood
- Sleep deprivation
- Photic stimulation with a stroboscope
- Alcohol withdrawal
- Drug withdrawal
Clinical features
Provoked seizures are almost always generalised tonic-clonic.
Treatment
Antiepileptics may be required acutely, but it’s not necessary to use antiepileptics for prevention long-term. It’s enough to avoid the provoking factor.
Symptomatic or occasional seizures
A symptomatic seizure is a seizure caused by a serious acute illness affecting the CNS. They can be thought of as symptoms of the underlying acute illness.
Etiology
- HSV encephalitis
- Autoimmune encephalitis
- Intracranial tumour (esp. meningioma)
- Traumatic brain injury
- Sinus thrombosis
- Ischaemic stroke
- Intracranial haemorrhage
- Metabolic disturbances (hypoglycaemia, hyponatraemia, hypernatraemia, …)
- Drug intoxication
- Sepsis
- Eclampsia
Rasmussen encephalitis is a rare autoimmune encephalitis which affects children. It affects only one hemisphere and causes seizures, hemiparesis, and unilateral cerebral atrophy. Prof. Pfund likes to ask about it.
Clinical features
Symptomatic seizures are usually generalised tonic-clonic seizures, but they can be any type.
Treatment
Symptomatic seizures may lead to status epilepticus and should be treated as such. Patients with symptomatic seizures sometimes require lifelong antiepileptics to prevent seizure recurrence, even if the underlying condition is treated, but in most cases there’s a low risk of recurrence.